Musnad Ishaq

Benefits:
It is a law of the Shari‘ah that when there is a dispute, the claimant must present evidence; if he does not present evidence, then the defendant must take an oath, as is mentioned in the hadith: ((Al-bayyinatu ‘ala al-mudda‘i wa’l-yaminu ‘ala man ankara.))... “The burden of proof (i.e., evidence, witnesses, etc.) is upon the claimant, and the oath is upon the one who denies.” (Bayhaqi: 8/123; Irwa’ al-Ghalil, no. 1938, its chain is authentic)

However, when the situation is such that both parties are claimants as well as defendants, then in such a case both have the right to take an oath. If both are willing to take the oath, then a lot will be drawn between them, and whoever’s name is drawn will take the oath and be deemed entitled to that thing. (Taraḥ al-Tathrib: 8/87)

Imam Khattabi rahimahullah says: By “compulsion” (ikrah) is not meant real compulsion, because no human can be forced to take an oath; rather, its meaning is that when the oath is presented to them and both are willing to take the oath, even if they inwardly dislike it. This is in the sense of recommendation (istihbab). In such a case, both of them are inwardly content to take the oath, and now their dispute is about who will take the oath first, so for taking the oath, a lot will be drawn between them, and this is what is meant by the statement of the Messenger of Allah sallallahu alayhi wa sallam. (Fath al-Bari: 5/352; Ma‘alim al-Sunan: 4/39)