Prepared under the guidance of Rabbi Sholom Ber Chaikin
The following is a short overview of the laws of Family Purity (Taharat Hamishpacha) and does not cover many crucial topics that an observant Jewish couple needs to know to keep these laws properly. If you would like to learn more about the laws of Family Purity please consider reading::
You can also watch our complimentary video tutorial to learn how to keep a mikvah calendar.
In-depth study with a qualified instructor and periodic review of all the laws of Taharat Hamishpacha remain essential. Every couple should carefully review the laws of Taharat Hamishpacha and the mikvah calendar (cheshbon calendar) at least once a year.
A luach is a Hebrew calendar. The purpose of a luach is to guide you in calculating and recording the times one is required to abstain from marital relations in anticipation of a menstrual flow.
Halacha (Jewish law) mandates the use of a Hebrew calendar to calculate the times required to abstain from marital relations in anticipation of a menstrual flow. The Hebrew date begins at shkiah (sunset) and ends the following day at shkiah (whereas the civil date, based on the standard solar calendar, begins and ends at midnight). All menstrual calculations are figured only according to the Hebrew calendar. Calculations based on any other calendar will not be accurate. Never use the standard solar calendar for this purpose although, for reference only, our online calendar and our print calendar include the civil dates.
An onah is a designated time frame. Each Hebrew calendar day is divided into two onot. The time between shkiah (sunset) and netz hachamah (sunrise) is known as the night onah, and the time between netz hachamah (sunrise) and shkiah (sunset) is known as the day onah. To simplify this concept, our online calendar, as well as in our print calendar, divide each day into two parts: the solid colored (shaded in the print calendar) area represents the night onah, and the lightly shaded (non-shaded in the print calendar) area represents the day onah. In order to accurately calculate your times of separation, it is important to correctly enter the onah (night or day) upon which your flow begins.
It is crucial to keep track of the exact times of sunset and sunrise for each day. This is very important since time determines which Hebrew date is to be counted as the date of the onset of the menstrual flow. It is also necessary to know exactly when a full five day count has been achieved so that the hefsek tahara may be attempted, and vital to determine which onah the period began so that the same onah will be observed as a time of separation. You can view these halachic times here. They are also noted on each day of our online calendar.
It is imperative to do these calculations yourself. Our Online Calendar can be used as a tool for learning how to keep a calendar as well as double checking your results. This is because there are halachic opinions that maintain that the obligation to record the onot of separation can not be fulfilled by a computer. Our Print Calendar used alone or in conjunction with our online calendar satisfies all requirements.
Most women expect their flow according to one or more of the following three types of cycles:
In anticipation of the coming menstrual flow, halacha requires husband and wife to abstain from marital relations during all time frames that correspond to these three types of cycles. It is praiseworthy to be strict and refrain even from embracing and kissing, and even more so, from sharing the same bed at these times. Regarding this stringency, the Alter Rebbe states in his Shulchan Aruch: "He who is stringent in this matter will be blessed." (A.R.S.A. chapter 184, note 6)
One should refrain from taking a bath or swimming on any onah of anticipation. Showering is permitted (so long as one does not wash internally). If one bathed before the required bedikah of an onah was performed, please consult your rav.
When a woman perceives or sees even a drop of blood discharged from her uterus, she is rendered nidah. All physical contact between husband and wife is forbidden during this time. Prior to resuming any physical contact with her husband, she is required to immerse in a kosher mikvah. Please note that blood resulting from the breaking of the hymen (dam besulim) and from childbirth, while rendering the woman nidah, has no bearing on the calendar and will not affect any calculations, nor create any onot of anticipation.
It is very important to realize that the rabbi is here for your benefit. The laws of Family Sanctity are sacred and complex, the rabbi is there to guide you. Do not try to decide things on your own. Bedikot, stains on garments or linens and situations you are unsure of, are reason to consult the rabbi.
If you are not sure whether you have a shayla (question regarding Jewish law), consult a qualified instructor for guidance. Mikvah attendants may be helpful. It is preferable to consult an Orthodox rabbi directly. However, if you are shy, the rabbi's wife, a mikvah attendant or qualified instructor may ask the rabbi for you. You need not and should not inspect toilet tissue after use. If you did and found something of a questionable color, you must save it and consult an Orthodox rabbi.
When in doubt, do not decide on your own that you are a nidah for it may halachically render you nidah unnecessarily. Conversely, do not decide on your own that you are not nidah.
How to Calculate
Each month you will anticipate your flow according to the same time and onah of the Hebrew date your menstrual flow began. If there is any staining preceding your period that you see but do not feel, although the Rav may determine it has made you nidah, for your calendar, day ONE of your flow is marked when the actual menstrual flow begins. If there is any staining preceding your period that you feel (any of the usual symptoms that tell you your period is coming) then that day is considered day ONE of your menstrual flow.
What to Record
On the Hebrew date upon which your menstrual flow begins, mark a letter “P” (for period) and record the time your period began. Be sure to mark the time including a.m. or p.m.
Then go to the following Hebrew month and find the same date. (Example, your period began on the 5th of Elul â€“ you will mark the 5th of Tishrei). You will mark this as the Veses HaChodesh time of separation. It will be a night onah of separation (from sunset to sunrise) if your period arrived anytime after shkiah (sunset) but before sunrise of the Hebrew date (remember that Hebrew dates begin at sunset the day before, so if the 5th of Elul was on a Monday, it would have begun after sunset on Sunday evening and will end at sunset on Monday evening), or it will be a day onah of separation if your period began anytime after sunrise but before sunset of that Hebrew date. Be sure to mark down the time as well, include a.m. or p.m.
Mark the date on your calendar on which you perform, and complete, a successful Hefsek Taharah before sunset with an HT. Draw a line from the “P” to the “HT”.
What to Carry Over
Any Veset Hachodesh dates that are determined and recorded on your calendar are canceled once they are passed clean, i.e. free of any spotting or bleeding on that actual date (Rabbonei Chabad).
Some Chabad Rabbonim maintain that once a Veset Hachodesh date is determined, it is recorded and carried monthly unless you do not see any blood that renders you nidah on that onah of anticipation (Kitzur Dinei Taharah 8:13). Accordingly, dates may need to be carried over for one or more months so you may have more than one date marked as a time of separation for the Veset Hachodesh on your calendar in any given month. (Any dates previously marked as Veset Hachodesh dates from previous flows that fall within the line drawn as described above from the “P” to the “HT” would then be carried to the following month)
Other Chabad Rabbonim, including Rabbi Yekusiel Farkash in Tahara K’Halacha, maintain that any Veset Hachodesh dates of anticipation that fall within your actual flow are NOT carried and are then canceled from your calendar.* (Any dates previously marked as Veset Hachodesh dates from previous flows that fall within the line drawn as described above from the “P” to the “HT” would now be canceled and not carried to the following month)
If you are uncertain of which rabbinical determination to follow, please consult your rabbi.
*Note: According to all Chabad Rabbonim, including Rabbi Y. Farkash, there may still be months where there are more than one Veset Hachodesh dates on your calendar.
Example: New Flow #1 begins on the 1st of Elul. Veset HaChodesh is then the 1st of Tishrei. New Flow #2 begins on the 15th Elul.
Because the 1st of Tishrei was not yet passed by a clean bedikah, nor did it fall into the bleeding days of the new flow, there will be two Veset HaChodesh days for the month of Tishrei, the 1st of Tishrei and the15th of Tishrei.
If your period began on the 30th day of the Hebrew month, lamed, and the following month there are only 29 days, the lamed is dropped with regard to the Veset HaChodesh.
You must abstain from marital relations during the full designated onah (either night onah or day onah) of every Hebrew date you have marked on your calendar that corresponds to the date a previous period began. It is praiseworthy to be strict and refrain even from embracing and kissing and even more so from sharing the same bed. The Alter Rebbe states in his Shulchan Aruch, "He who is stringent in this matter will be blessed." (A.R.S.A. chapter 184, note 6)
Make a bedikah on each onah on which you anticipate a flow. Your bedikah should be made preferably just AFTER the time of day your flow began that created the Veset Hachodesh or sometime later on, but before the end of the onah. If the bedikah is clear or white, physical intimacy may resume only after the onah has ended. (p. 37 Kitzur Dinei Tahara)
How to Calculate
Count four weeks and one day from the beginning of your last flow. Start the count with the day your last flow began. For example, if your flow started on either Sunday night (the night onah of Monday) or on Monday between sunrise and sunset, then four weeks later on Tuesday is the Onah Beinonit. It is exactly day 30 from your last flow (onset of flow being day 1).
What to Record
Mark the entire day 30 (both night and day onot) Â as the Onah Beinonit time of separation. The Onah Beinonit is a full 24 hour time of separation.
What to Carry Over
The Onah Beinonit is never carried over; it is calculated as the 30th day from each new flow.
Older Onah Beinonit dates are dropped from the calendar.
You must abstain from marital relations for two full onot, (night and day) from shkiah to shkiah (24 hours) on the Hebrew date marked as day 30. It is praiseworthy to be strict and refrain even from embracing and kissing, and even more so from sharing the same bed. The Alter Rebbe states in his Shulchan Aruch, "He who is stringent in this matter will be blessed." (A.R.S.A. chapter 184, note 6)
Make a bedikah before shkiah (suggested time is ten minutes prior to shkiah) at the end of the Onah Beinonit. If the bedikah is clear or white, physical intimacy may resume only after the Onah Beinonit has ended.
[For those women for whom making bedikot pose no difficulty, it is a chumrah (optional stringency) to make another bedikah after tzait hakochavim (nightfall) following the end of the Onah Beinonit. Tahara K'Halacha, by Rabbi Yekusiel Farkash.]
Please Note: A woman has a halachic obligation to inform her husband of the Onah Beinonit and to notify him that she has done the bedikah to cancel the day. If she does not inform him, it is the husband's obligation to ask. If she forgot to make a bedikah, a Rav should be consulted.
How to Calculate
Haflaga is the interval of onot between a successful hefsek tahara and the subsequent menstrual flow. The haflaga is customarily counted beginning with the night onah immediately following the hefsek tahara and terminating with the onah on which the following flow begins. Each date consists of two onot â€“ a night onah followed by a day onah. You will have a count of two onot for each date, beginning with the date immediately following your successful Hefsek Tahara and ending your count with the onah upon which your flow begins. Calculating by this method, the haflaga number is an odd number if the flow begins at night, and the separation will be during a night onah. The haflaga number is an even number if the flow begins during the day, and the separation will be during a day onah. The haflaga numbercan be calculated only once there is a successful Hefsek Tahara and then the onset of a subsequent period. The recording of the haflaga onah/ot onto the calendar, however, can only occur once the subsequent Hefsek Tahara has been successfully completed.
Some people compute the haflaga by counting the onot from the onah immediately following the hefsek taharah up to and including the onah immediately BEFORE the new flow. When figuring the haflaga onah/ot, they abstain on the onah that immediately follows the end of their count. This coincides with the haflagh onah designated by the method explained in the main text. However, calculating by this alternative method will give an even number indicating separation during a night onah and an odd number indicates separation on a day onah. Regardless of how one calculates the haflaga, the onah of separation remains the same, only the number is different.
What to Record
Mark your calendar with “HT” on the day you perform and complete a successful hefsek tahara before sunset, as explained above.
Count out the onot, each day consisting of two (night and day), beginning with first date following the successful hefsek tahara of your previous period. End the count on the date your next period begins. Mark this number down next to the “P” noting the onset of your period. This is your haflaga number. Remember that you will have an odd number for a period that began on a night onah and an even number for the period that began during the day onah.
When you complete your next hefsek tahara, mark the new “HT” onto your calendar on the date it was done (as explained above).
Beginning with the date immediately following that new hefsek tahara, count the same number of onot (each day consisting of two).
Mark the date upon which your count ends with the haflaga number. Make note of the time your period began that created this haflaga number, including a.m. or p.m. This is your haflaga onah of separation.
Repeat this process with each haflaga number on your calendar. (see below What to Carry Over)
What to Carry Over
Each time a haflaga number is determined, it is always recorded for the current month. It remains on your calendar and is carried over monthly until a subsequent period gives you a greater haflaga number. At that point the greater number cancels all previous haflaga numbers that are smaller than it.
In other words, if your flow comes after any date/s marked with haflaga numbers (haflaga onot), the haflaga numbers corresponding to those dates are cancelled, marked with an “X” and are not carried over to the following month.
What if your flow comes after some date/s marked with haflaga numbers (as explained above), but before other, later, date/s on your calendar marked with haflaga numbers?
Those later date/s marked with haflaga numbers are disregarded for the present and do not require separation and bedikot. However, the haflaga numbers on those later date/s are not cancelled. Those haflaga numbers are carried over to the following month and must be marked onto new dates recalculated from the newest hefsek tahara. If your flow begins on a date marked with a haflaga number, its corresponding number is also carried over to the following month. The next date of this haflaga number will be a different one. You will calculate the new date after the next hefsek tahara has been successfully completed.
To paraphrase the above, all previous haflaga numbers greater than or equal to the current month's haflaga number are carried over to the following month. The dates corresponding to those haflaga numbers will be recalculated from the newest hefsek tahara. Those dates will be marked with the corresponding haflaga numbers as explained. Any numbers lower than the current month's haflaga number are cancelled.
You must abstain from marital relations during the full designated onah of every Hebrew date marked with a haflaga number, as long as a new flow did not precede it. Remember that any date marked with an odd number (if counting by the method in the main text â€“ opposite if counting by the method in the Note) means a separation from sunset to sunrise of that Hebrew date (i.e. if the date marked with an odd number is a Monday, then separation would be from sunset Sunday to sunrise Monday morning). Any date marked with an even number means a separation from sunrise to sunset of that Hebrew date (i.e. if the date marked with an even number is a Monday, then separation would be from sunrise Monday morning to sunset Monday evening). It is praiseworthy to be strict and refrain even from embracing and kissing, and even more so from sharing the same bed. The Alter Rebbe states in his Shulchan Aruch, "He who is stringent in this matter will be blessed." (A.R.S.A. chapter 184, note 6)
Make a bedikah on the designated onah of every Hebrew date marked with a haflaga number, as long as a new flow did not precede it and thus cancel the date - though it does not cancel the haflaga number corresponding to that date. Your bedikah should be made preferably just after the time of day you experienced your previous flow/s that created each haflaga number or sometime later on, but before the end of the onah. If the bedikah is clear or white, physical intimacy may resume only after the onah has ended. (p. 37 - Kitzur Dinei Tahara)
A woman with a veset kavuah (established pattern) should consult a Rav on how to keep her calendar during pregnancy. A woman with no veset kavuah needs to keep the onot of separation that fall within the first three months of pregnancy (calculating from mikvah immersion).
Once she has observed them, she does not carry any of them over.
This means that she needs to keep one onah beinonit, any veset hachodesh dates (these will all be passed in the first month) and all haflaga onot that fall within the first three months of the pregnancy. She does not keep a calendar again until she will have her first period post birth. She also does not have to keep any larger haflaga onot that may fall past the first three months of the pregnancy.*
Any woman that has any staining or bleeding at any time during the pregnancy MUST consult a Rav and be certain to ask him if/how this affects her calendar.
If you are experiencing difficulty becoming pregnant it is essential that you consult with a knowledgeable Rav. To contact a Rabbi for guidance in matters of fertility please call 347-470-3130 or email email@example.com. The Rabbonim are under the direction and endorsement of Rabbi Y. Farkash, Rabbi Y. Feigelstock and Rabbi Y. Ulman. Confidentiality is assured.
How to determine whether a Veset Kavua (established pattern) exists
Although not common, some women can halachically establish a veset kavua. If after several periods you notice any uniformity, progression or pattern (e.g. your period begins on the 15th of every Hebrew month during the daytime three times in a row), or if you have any doubt, consult a Rav to determine whether or not you have established a veset kavua. Once a set menstrual cycle is established, special halachot apply. A Rav or qualified instructor must be consulted.
For 24 months post birth (or r”l a miscarriage of a pregnancy of 40 days or longer duration) kavua is not an issue and the calendar must be kept as for one who does not have a kavua pattern.
Some important notes:
A. If you are not sure whether you have a shayla (question regarding Jewish law), consult a qualified instructor for guidance. Mikvah attendants may be helpful.
B. It is preferable to consult a Rav directly. However, if you are shy, the Rav’s wife, a mikvah attendant or qualified instructor may ask the Rav for you.
C. You need not and should not inspect toilet tissue after use. If you did and found something of a questionable color, you must save it and consult a Rav.
D. If your period comes at a time when Daylight Saving Time (or the reverse) or any other time changes caused by normal seasonal changes would change the onah, keep the onah, and disregard the time. A night onah remains a night onah and day onah remains a day onah.
Period arrives at 5:50 pm on the day onah of the 18th of Cheshvan. The veset hachodesh is therefore the day onah of the 18th of Kislev.
On the 18th of Kislev, however, sunset is at 4:32 pm, due to the return to Standard Time from Daylight Savings Time. This puts 5:50 pm into the night onah.
In this case, disregard the time, separate for the entire day onah and perform the necessary bedikah just before the end of the onah (just before sunset) on the 18th of Kislev.
Period arrives at 7:35 pm on the night onah of the 1st of Nisan. The veset hachodesh is therefore the night onah of the 1st of Iyar.
On the 1st of Iyar, however, sunset it at 7:55 pm, according to the normal seasonal change of time. This puts 7:35 pm into the day onah.
Again, in this case, disregard the time, separate for the entire night onah and perform the necessary bedikah before the end of the onah (sunrise) on the 1st of Iyar.
E. If at any time you forgot to do a bedikah at the proper time, do it as soon as you remember. If the bedikah is clean, you may cancel the date. If the bedikah is not clean, ask a Rav how it affects your calendar.
F. When the Veset Hachodesh date of anticipation coincides with Onah Bainonit dates; if the Chodesh onah is a night onah, do a bedikah to cancel out the Chodesh night onah (after the time of onset of the period that set the onah, but before sunrise). If the Chodesh onah is a day onah, if the time of the Veset HaChodesh onah is close to the time when you must do the bedikah for the Onah Beinonit (just before shkiah), one bedikah can cover both (Veset HaChodesh & Onah Bainonit). If the time of the Veset HaChodesh onah is far from the time before shkiah (e.g. in the morning, etc) and doing a bedikah poses no difficulty, then a bedikah should be done to cancel out the Veset HaChodesh date, and another just before shkiah for the Onah Beinonit.
G. If you experience any New Flow that lasts less then 24 hours, consult a Rav regarding the onot of separation that may result from this flow.