Certainty is never annulled except by certainty; it can never be annulled by mere doubt – Shaykh As-Sa’di | Dr. Saleh As-Saleh
Al-Qawaa’id wal-Usool al-Jaami’ah wal-Furooq watTaqaaseem al-Badee’ah an-Naafi’ah
The Basic Rulings and Principles of Fiqh
The Beneficial, Eloquent Classifications and Differentiations
By Sh. ‘Abdur Rahmaan ibn Naasir As-Sa’di (rahimahullaah)
Discussion based upon:
1-Sh. Ibn Sa’di’s original explanation
2-Our Sh. Muhammad ibn Saalih Al-‘Uthaimeen’s Commentary, and
3-Full explanation by our Sh. (Dr.) Sami ibn Muhammad As-Sghair (summer 1427 A.H./2006 C.E.)
All Praise is due to Allaah, and may the salaah and salaam be on Prophet Muhammad, his household, the noble companions, and those who follow them until the Day of Resurrection. This is a continuation of the explanation of The Basic Rulings and Principles of Fiqh – The Beneficial, Eloquent Classifications and Differentiations by Imaam ‘Abd ar-Rahman bin Naasir as-Sa’di (rahimahullaah).
Foundation eleven is entitled:
The asl (i.e. previous state or condition) remains in effect, and certainty is not annulled by mere doubt.
This great foundation covers many matters including:
1) Acts of worship
2) Salaah (prayer)
6) Nikaah (marriage)
Evidence for Foundation 11
This foundation is established on the authentic hadeeth from ‘Abbaad bin Tamim ( radiyallaahu ‘anhu):
“My uncle (radiyallaahu ‘anhu) asked Allaah’s Messenger (sallallaahu ‘alayhi wa sallam) about a person who imagined to have passed wind during the salaah. Allaah’s Messenger (صلى الله عليه وسلم) replied: ‘He should not leave his salaah unless he hears sound or smells something.’” 
Therefore, the person should not discontinue his prayer due to mere doubt. He should only leave when he is certain he has invalidated his state of purity.
1) A person makes wudhu and later doubts whether he performed an act that would nullify it. In such a situation, the asl is the existence and continuity of purity. The fact that he thinks he may have done a ritual impurity is not to be considered as in origin, the person was in a state of purity. Certainty is never annulled except by certainty; it can never be annulled by mere doubt. Rather, it is strange that some people when they have doubts, they experience whispering which drives them to remove the doubt with certainty by intentionally invalidating their wudhu.
2) A person was certain that he was in a state of ritual impurity. Later, he doubts whether he made wudhu. In this case, the asl is that the state of ritual impurity remains in effect.
Therefore, the asl remains, and it does not cease except when there is certainty that renders it annulled.
Doubt in the Purity of an Object
Purity (at-tahaarah) is the origin of things (e.g. water, clothing, etc.); whenever someone doubts the purity of something, then he builds upon the asl that it is pure. For instance, if some water from a drain falls on him or he steps in moisture, then the origin is that this water is pure. However, if someone is sure filth has fallen on his garment but later doubts whether he washed it, then the asl is that the ritual impurity remains.
Doubt in the Number of Completed Rakaah in Salaah
In salaah, a person may doubt exactly how many rakaah he has performed. Such situations are divided into two categories: preponderance and total doubt. For example, if someone doubts how many rakaah he has already prayed (e.g. three or four units) but preponderates a certain number, then he builds on that preponderance and later makes two prostrations of forgetfulness (sujuud as-sahw).
The evidence for relying on preponderance came in the sunnah from the hadeeth of Abdullaah bin Masood (radhi Allaahu anhu):
“The Prophet (صلى الله عليه وسلم) prayed [and the subnarrator Ibrahim (rahimahullaah) said, ‘I do not know whether he prayed more or less than usual’], and when he had finished the prayers he was asked, ‘O Messenger of Allaah! Has there been any change in the prayers?’ He (صلى الله عليه وسلم) said, ‘What is it?’ The people said, ‘You have prayed so much and so much.’ So the Prophet bent his legs, faced the qiblah and performed two prostrations (of sahw) and finished his prayers with tasleem (by turning his face to the right and left saying: ‘As-salaamu ‘alaykum wa rahmatullaah’). When he turned his face to us, he (صلى الله عليه وسلم) said, ‘If there had been anything changed in the prayer, surely I would have informed you, but I am a human being like you and liable to forget like you. So if I forget, remind me and if anyone of you is doubtful about his prayer, he should follow what he thinks to be correct (falyataharra as-sawab) and complete his prayer accordingly and finish it and do two prostrations (of sahw).’” 
However, when a person is in total doubt concerning how many rakaah he has already completed (e.g. two or three), then he builds upon certainty which is the lesser number; he then makes sujuud as-sahw.
1) A person is unsure whether he prayed three or four rakaah and is unable to determine which is more likely. He should therefore build on certainty which is the lesser number (i.e. three) and make sujuud as-sahw.
2) A person is not certain whether he prayed three or four rakaah but preponderates that he prayed four. He should therefore build on the preponderance (i.e. four rakaah) and make sujuud as-sahw.
In addition, preponderance is used to determine the number of completed rounds in tawaaf and walks in saa’ee between Safa and Marwah. For instance, if a person is in total doubt as to whether he completed six or seven walks in saa’ee, then he builds on certainty and considers it to be as if he made six trips. Similarly, if he is able to preponderate that it is the sixth walk, then he should consider it the sixth and bring the seventh. However, there is no sujuud as-sahw legislated for tawaaf or saa’ee given the weakness of the narration from ibn ‘Abbaas (radhi Allaahu anhu) that the tawaaf is salaah. This foundation also is applicable to washing a utensil seven times after a dog has licked it. If someone is entirely unsure whether he washed it three or four times, then he builds upon certainty, but if he is able to preponderate, then he builds upon that.
Doubt in the Number of Missed Prayers and Fasts
When making up missed prayers or days of fasting, the person builds on certainty. However, this can be problematic. For instance, someone is unsure whether he broke his fast three or four days in Ramadan. In principle, he is certain he broke it at least three times. However, this origin is opposed by another asl, which is the obligation to fulfill that which is binding upon one’s self. This can not be attained except by fasting four days.
Similarly, if someone does not know if he missed five salaah or six, then in origin he certainly missed at least five, but this is in opposition to the obligation to free one’s responsibility. This can not be fulfilled except by performing six. In this case, he brings that which is higher.
Doubt Concerning which Specific Prayer was Missed
If someone knows that he missed one salaah on a given day but does not remember which prayer (e.g. duhr, ‘asr, etc.), then there are the following opinions concerning that:
1) The person should pray all five prayers because it is possible the missed salaah is any one of them.
2) He should pray one salaah with four rakaah, another salaah with three rakaah, and one salaah of two rakaah. This is because the salaah of four rakaah would cover for duhr, ‘asr, and isha’ while the other two salaah would cover for maghrib and fajr respectively.
3) Our Shaykh, Muhammad bin Saalih al-Uthaymeen (rahimahullaah) said, “He should exert the effort until he preponderates which is the correct one.” If the person sincerely attempts to recall which salaah he missed, Allaah (subhaanallaahu wa ta’aalaa) will let him remember.
Doubt in Divorce
There are many different situations in which doubt in divorce can occur. They include:
1) A person doubts whether he uttered the statement of divorce at all. In this situation, the asl is that he did not say it, and the couple is still married. This is because the marriage is certain and is not annulled by mere doubt.
2) If someone doubts whether he conditioned the divorce on something, then the asl is that the divorce is unconditional.
3) Someone conditions his divorce on some matter. Later, he doubts whether the condition was fulfilled. The origin therefore is that it did not take place.
4) A person divorced his wife but is uncertain how many times he uttered the statement (i.e. once, twice or thrice). The asl is that he said it once.
5) A man has two wives (for example Hind and Fatimah), and he doubts which of his wives he uttered the divorce concerning. This matter should be decided by drawing lots. If the lot came on Fatimah, then she is divorced, and Hind remains his wife. If he later remembers he actually divorced Hind or found a paper documenting that, then he leaves Hind and returns Fatimah as long as the drawing of the lots and the accompanying decree was not issued by a judge (if it was performed by a judge, then it would be classified as the judge’s direct ruling). However, if Fatimah got married to someone else in the meantime, then the husband can not return Fatimah because she is now the right of her new husband unless he brings proof, such as a document with testimony, that the divorce was for Hind; in this case, Fatimah can return to him.
6) A person doubts whether his wife finished her waiting period. The asl is that she has not finished it and is still in her ‘iddah.
Doubt in Suckling
Concerning suckling, doubts affect whether or not there is prohibition (tahreem) to marry the wet nurse and her daughters. Cases include:
1) Doubt exists concerning whether a particular child nursed from a woman at all. The asl in this situation is that he did not.
2) Someone doubts whether he suckled from a woman five times or less than that. This person builds upon certainty, which is that he suckled on less than five occasions.
3) There is doubt around when a child suckled from a wet nurse. In this matter, the scholars have two opinions.
a. Some scholars hold that for tahreem to exist, the child must have suckled within the first two years. If there is doubt as to whether a child suckled from a woman within the first two years, then in principle the asl would be that he suckled within that period, which would entail tahreem. However, the scholars have explained that since this asl leads to tahreem, the origin is that there is no forbiddance.
b. Other scholars have mentioned that the condition for tahreem is whether the child suckled before or after weaning. If there is doubt as to whether the child suckled before or after weaning, then in principle the asl would be before weaning. However, just as with the other opinion, the scholars have explained that in origin there is actually no forbiddance in this case.
Thus, with either opinion, there is no tahreem.
4) A mother is certain that a woman in a particular household nursed her child but is unsure as to which specific woman did it. In this case, the tahreem is upon all of the women in the household. For example, if there are two women in that house, then both women and their daughters are haraam for him to marry.
5) A woman is certain that she nursed a child in a particular household but is unsure as to which child. Therefore, it is as if she nursed all of them. Hence, all of the boys of this house are prohibited from marrying her as well as her daughters, and they become mahaarim (pl. of mahram) for her and her daughters.
Doubt in the Hunting of Game
When a person is hunting game, doubt can exist concerning whether the animal was killed by his shot or some other cause. Such situations are divided into two categories.
1) No cause is found for the death of the animal other than the shot. Therefore, the meat is halaal.
Example: Someone says the basmalah and shoots an animal. He later finds the animal dead with no sign of another cause for its death. As such, the asl is the nonexistence of another cause, which makes the meat halaal.
2) Another cause is found for the animal’s death that is equally or close to equally as likely as the shot to have killed it. Therefore, the meat of the animal is haraam. This is proven by the hadeeth of Adi bin Hatim (radhi Allaahu anhu) that the Messenger (صلى الله عليه وسلم) said,
“When you set off your dog, recite the name of Allaah, and if it catches (game for you) and you find it alive, then slaughter it. If you find it dead and that (your dog) has eaten nothing out of that, (even then) you may eat it, but if you find along with your dog another dog and a kill has been made, then do not eat, for you do not know which of the two has killed it. And if you shoot your arrow, recite the name of Allaah, but if it (game) goes out of your sight for a day and you do not find on that but the mark of your arrow, then eat that it you so like, but if you find it drowned in water, then do not eat that.” 
Example: A person shot an animal, but the shot did not kill it immediately. The animal was later found dead in a pool of water. It can not be known whether the shot killed the animal or it drowned. Thus, as proven by the hadeeth of Adi (radhi Allaahu anhu), this meat is forbidden.
Under this foundation many matters fall; anyone that studies fiqh will surely be benefited by it and will be better able to relate matters to their principles and origins. In summary, the continuity of the asl remains whenever the existence of a cause to nullify it is doubted. Similarly, in every matter where there is a doubt about the number, we build on preponderance, and if there is no preponderance, then we build on certainty.
The eleventh foundation in Imaam ‘Abd ar-Rahman bin Naasir as-Sa’di’s book, al- Qawaa’id wal-Usool al-Jaami’ah wal-Furooq wat-Taqaaseem al-Badee’ah an- Naafi’ah (The Basic Rulings and Principles of Fiqh – The Beneficial, Eloquent Classifications and Differentiations), is entitled:
The asl remains in effect, and certainty is not annulled by mere doubt.
All Praise is due to Allaah, and may the salaah and salaam be on Prophet Muhammad, his household, the noble companions and those who follow them until the Day of Resurrection.
 Agreed upon. Reported in Saheeh al-Bukhaari (English translation vol. 1, hadeeth no. 139) and with a similar wording in Saheeh Muslim (English translation no. 702, book 3).
 Reported in Saheeh al-Bukhaari (English translation vol. 1, hadeeth no. 394).
 Agreed upon. Reported in Saheeh Muslim (English translation no. 4741, book 21) and with a similar wording in Saheeh al-Bukhaari (English translation vol. 7, hadeeth no. 384, 385, 386, 392, 393, 394, & 395).