`Sayyiduna Umar bin Khattab (may Allah be pleased with him) says that the Messenger of Allah (peace and blessings be upon him) said that Allah Almighty forbids you from swearing by your forefathers. Sayyiduna Umar (may Allah be pleased with him) said: By Allah! Since I heard this from the Messenger of Allah (peace and blessings be upon him), I have not sworn by (my forefathers), neither on my own behalf nor while quoting someone else.

`Sayyiduna Ibn Umar (may Allah be pleased with them) narrates that the Messenger of Allah (peace and blessings be upon him) said: Whoever wants to swear an oath should not swear by anyone except Allah. And the Quraysh used to swear by their forefathers, so the Messenger of Allah (peace and blessings be upon him) said: Do not swear by your forefathers.

`Sayyiduna Abdur Rahman bin Samurah (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: Do not swear by idols, nor by your forefathers.

Abu Huraira (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings of Allah be upon him) said: If any of you swears by saying, "By Lat!", he should say, "There is no god but Allah." And whoever says to another, "Come, let us gamble," he should give charity. In one narration, along with "Lat," "Uzza" is also mentioned.

Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates from the Noble Prophet (peace and blessings be upon him) that he said: The Prophet of Allah, Sulaiman bin Dawud (peace be upon them), said: "Tonight I will go to seventy women" (in one narration it is ninety, in another ninety-nine, and in another one hundred), "each of whom will give birth to a boy who will fight in the way of Allah." His companion or an angel said to him: "Say, InshaAllah (if Allah wills)." But he did not say it; he forgot. Then none of the women gave birth except one, and she gave birth to a half-formed child. The Messenger of Allah (peace and blessings be upon him) said: "If he had said InshaAllah, his statement would not have been rejected and his intention would have been fulfilled."

`Sayyiduna Abu Huraira (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: The meaning of an oath will be according to the intention of the one who administers the oath.

Narrated from Sayyiduna Abu Umamah (i.e., Harithi) رضي الله عنه that the Messenger of Allah صلى الله عليه وسلم said: Whoever seizes the right of a Muslim (whether it is wealth or something other than wealth, such as the skin of a dead animal, dung, etc., or other types of rights such as the right of pre-emption, the right to water, the punishment for slander, the turn to stay with the wife, etc.) by swearing an oath, Allah Almighty has made Hell obligatory for him and has forbidden Paradise for him. A man said, "O Messenger of Allah! Even if it is a small thing?" The Prophet صلى الله عليه وسلم replied, "Even if it is only a twig of the arak tree."

‘Sayyiduna Wa’il bin Hujr (may Allah be pleased with him) narrates that a man from Hadhramaut and a man from Kindah came to the Messenger of Allah (peace and blessings be upon him). The man from Hadhramaut said,“O Messenger of Allah! This man has seized my land which belonged to my father.”The man from Kindah said,“It is my land, it is in my possession, I cultivate it, he has no right in it.”The Messenger of Allah (peace and blessings be upon him) said to the man from Hadhramaut,“Do you have any witnesses?”He replied,“No.”So the Prophet (peace and blessings be upon him) said,“Then take an oath from him.”He said,“O Messenger of Allah! He is a wicked man, he does not fear taking a false oath, and he does not care about anything, he can easily swear.”The Prophet (peace and blessings be upon him) said,“This is all that is possible for you from him.”When he went to take the oath, the Messenger of Allah (peace and blessings be upon him) said to him as he was leaving,“Beware! If he swears an oath to unjustly take the property of another, he will meet Allah while Allah will turn away from him.”

Sayyiduna Abu Musa Ash'ari (may Allah be pleased with him) says: I came to the Messenger of Allah (peace and blessings be upon him) along with some Ash'aris to ask him for mounts. The Messenger of Allah (peace and blessings be upon him) said, "By Allah, I will not give you mounts, and I do not have any mounts to give you." Then we stayed there for as long as Allah willed. After that, some camels came to the Messenger of Allah (peace and blessings be upon him), so he ordered that three white-humped camels be given to us. When we left, we or some of us said, "May Allah not bless us, for we came to the Messenger of Allah (peace and blessings be upon him) and asked for mounts, and he swore that we would not get mounts, but then he gave us mounts." Then people came to the Messenger of Allah (peace and blessings be upon him) and told him, so he said, "I did not mount you, but Allah mounted you. And if I ever swear an oath and then see something better than it, I will offer expiation for my oath and do what is better."

Abu Huraira (may Allah be pleased with him) reports that a man was delayed at night with the Messenger of Allah (peace and blessings be upon him), then when he went to his home, he saw that his children had fallen asleep. His wife brought food, so he swore an oath that he would not eat because of his children. Then he thought it appropriate to eat and so he ate. Later, he came to the Messenger of Allah (peace and blessings be upon him) and informed him, so the Messenger of Allah (peace and blessings be upon him) said: Whoever swears an oath about something, but then sees something else better than it, should do that which is better and give expiation for his oath.