Nathr is a vow or pledge made to Allah Ta’ala. Nathr Saum is a pledge to fast. A person may make a vow that if a certain dua or wish is granted, a certain number of days will be fasted. On the materialization of the dua/wish, fulfillment of the vow becomes Wajib (compulsory).
Nathr Saum is of two kinds:
(1) Nathr Mu-ayyan and (2) Nathr Ghair-muayyan or Nathr Mutlaq.
Nathr Muayyan is a vow in which the pledge is made to fast on specific days, e.g. it is pledged: “O Allah! if my dua Is fulfilled, I shall fast next Thursday, Friday and Saturday”.
On fulfillment of the dua, it becomes W5jib to fast on the specific days mentioned in the vow.
(2) Nathr Mu-ayyan belongs to the first category of Saum, viz. the wajib category.
(3) Niyyat for Nathr Muayyan will be valid until Nisfun-Nahar.
Nathr Ghair Muayyin or Nathr Mutlaq is a vow in which specific days are not set aside for Saum. The number of days to be fasted is declared, but the intention is not to fast on any particular days, e.g. a person vows:
“O Allah! if a certain dua of-mine is fulfilled, I shall fast three days”.
Or someone merely assumes the liability of fasting a number of days without conditioning the fast with fulfillment of a dua, e.g. one says:
“O Allah! I shall fast two days”.
(5) The saum of Nathr Mutlaq may be kept at any time. One is not required to keep such Saum immediately although it is best to discharge the obligation as soon as possible since no one knows when maut (death) will overtake one.
(6) For the validity of the Saum of Nathr Mutlaq it is essential to make niyyat before Subah Sadiq. If niyyat for this type of fasting is made after Subah Sadiq, the saum of the Nathr will not be discharged and the fast thus kept will be a Nafl one. The fast of the Nathr will have to be discharged on another day with a niyyat made before Subah Sadiq.
(7) When the method of executing the fasts is not stipulated in the vow, it will be permissible to discharge the Saum of the Nathr in any way one pleases, whether consecutively or interspersingly. Example: A vow is made to keep 10 fasts. When the vow was made one did not have any intention of keeping the fasts one after the other (i.e. consecutively) nor of keeping the fasts spread over a period (i.e. interspersingly). In this case one has the choice of executing the Saum consecutively or interspcrsingly.
(8) When the intention is to keep the Saum of the Nathr consecutively then it will be obligatory to do so.
(9) When failing to observe the consecutive order (as mentioned in mas’alah 8), the Saum will have to be kept all over again, e.g. the intention at the time of the vow was to fast three consecutive days. However, after fasting two days, one failed to observe fast on the third day or haidh started. The Saum will have to be started over again.
(10) If on account of severe weather conditions, e.g. extreme heat, one is unable to execute the Saum of Nathr on its specific days, it will be permissible to postpone the fasting for the winter months. The qadha will be valid.
(11) If the Nathr of Saum is attached to a condition, the fast will be validly executed only after the coming into effect of the condition. Example: “I shall fast three days if a certain event occurs”. Now, if one fasts before the event transpires, the Saum of the Nathr will not be discharged. After occurrence of the event, the fasts will have to be repeated.
(12) Unfulfilled Saum of Nathr must be compensated by Fidyah, i.e. when death overtakes one, wasiyyat to pay Fidyah has to be compulsorily made. Example: A man vows to fast one month. Before being able to complete the month’s fasting, he is overtaken by severe illness and he loses hope in life. It now becomes obligatory on him to make a bequest (wasiyyat) to enable his heirs to pay the Fidyah of the unfulfilled number of days of his Nathr.
(13) A vow of fasting made during the state of illness will become binding only if one gains sufficient health to fast. Thus, if a man during his illness vows to fast for a number of days, but dies before recovering from that illness, he is under no obligation to make wasiyyat for the payment of Fidyah for the Saum he was unable to execute. Fidyah is not Wajib on him.
However, if he recovers from his illness for even one day, the full number of days of his vow becomes obligatory on him. If he thereafter again lapses into sickness and loses hope in life, he has to make wasiyyat for the payment of Fidyah.