Allah has mentioned the term “oath” in several places in His Book. He, Most High, says:
“Detain them both after the prayer and, if you have doubts, let them swear by Allah: ‘We will not exchange this oath for any price, even for a near relative, nor will we conceal Allah’s testimony; otherwise, we would surely be among the sinful.’”
Then, further on:
“Then let two others take their place—the two nearest of kin among those entitled to a claim—and let them swear by Allah: ‘Our testimony is truer than theirs, and we have not transgressed; otherwise, we would surely be among the wrongdoers.’”
“That makes it more likely that they will give testimony properly, or fear that other oaths will be sworn to refute their own.”
In Sūrat Barā’ah, when discussing treaties with the polytheists, He, Most High, says:
“Then fight the leaders of disbelief, for they have no regard for oaths, so that they may desist.”
“Will you not fight a people who broke their oaths and plotted to expel the Messenger, and who attacked you first?”
He, Most High, also says:
“Fulfil the covenant of Allah when you make a covenant, and do not break oaths after confirming them, having made Allah your guarantor. Indeed, Allah knows what you do.”
“Do not be like the woman who unravelled her yarn after spinning it firmly, using your oaths to deceive one another because one community is greater than another. Allah only tests you through this.”
He, Most High, says:
“They swear by Allah their most solemn oaths that, if a sign came to them, they would surely believe in it.”
He, Most High, says:
“They swear by Allah their most solemn oaths that Allah will not resurrect those who die.”
He, Most High, says:
“They swear by Allah their most solemn oaths that, if you commanded them, they would surely go forth. Say: ‘Do not swear; proper obedience is what is required.’”
The lexicographers state—and these are al-Jawharī’s words—“Yamīn means an oath. Its plurals are aymun and aymān.” He then says: “It was so named because, when people pledged themselves to one another by oath, each would grasp the other’s right hand.”