“I will not swear,” we do not rule against him, nor do we say, “You must pay the zakah,” because this is a right owed to Allah, and a person’s worship is a matter between him and his Lord. This is the general principle: no oath is administered concerning what pertains to the rights of Allah, whereas an oath is administered concerning what pertains to the rights of people. There are, however, matters that lie between the right of Allah and the right of people; regarding these, there is generally disagreement among the scholars.
As for whether an oath in legal claims serves to settle the dispute or to absolve one of liability, we have previously stated that it serves to settle the dispute. Thus, if the defendant swears an oath and the claimant subsequently produces evidence, judgment is made in the claimant’s favor on the basis of his evidence. The oath does not extinguish the right; it merely settles the dispute.
His statement: “No oath is administered concerning acts of worship.” The basic principle is that no oath is administered concerning any act of worship. Thus, if someone is told, “You did not pray,” and he says, “I did pray,” we do not require him to swear an oath, because this concerns a right of Allah. Likewise, if someone is asked, “Did you fast?” and he says, “Yes,” and we say, “You did not fast,” but he replies, “Rather, I did fast,” we do not require him to swear an oath. The same applies to zakah. If we ask, “Did you pay your zakah?” and he says, “I paid it,” we do not require him to swear an oath. Should we ask, “To whom did you pay it?” The answer is no. But if he says, “I paid it to so-and-so,” and we know that this person was wealthy at the time, we say: “Take it back from him.”
His statement: “Nor concerning the prescribed punishments of Allah.” Likewise, a person is not required to swear an oath in such cases. What is meant by the prescribed punishments of Allah is that which entails a fixed legal punishment. Thus, if someone is told, “You committed unlawful sexual intercourse,” and he says, “I did not commit unlawful sexual intercourse,” we do not say, “Swear an oath,” because if he refuses to swear, we would not subject him to the fixed punishment. We do not impose that punishment on him unless he confesses and persists in his confession until the punishment is carried out.