the practice in qasāmah (the procedure of sworn oaths in an unresolved homicide): the heirs of the slain person swear against the alleged killer even though they did not see him, on the basis of their predominant belief.
The same applies if a person swears about a future event which he expects to occur, but it does not occur. For example, he says, “By Allah, Zayd will arrive tomorrow,” but Zayd does not arrive. Nothing is due from him, because when he said, “By Allah, Zayd will arrive tomorrow,” he did not intend either to bind himself or to impose an obligation; rather, he was merely stating what he believed in his heart—whether Zayd arrived or not. Even if he did not arrive, and the man were asked, he would say: “Yes, I thought that he would arrive. I only ever swore about something when I expected it to happen, and I continued to expect it until the sun set.”
Likewise, if it involved divorce and he said, “Upon me be divorce: Zayd will arrive tomorrow,” but Zayd did not arrive, while his intention was merely to convey information—not to oblige Zayd to arrive, nor to bind himself to bring about his arrival—then he has not broken his oath. This is the correct view in this matter: the basic principle is that acts of worship are based on predominant belief, and Allah does not burden any soul beyond its capacity.
His statement: “If he does part of it, he has not broken his oath unless he intended it.” If someone swears that he will not do something, but does part of it, he has not broken his oath unless he intended that part; if he did intend it, then he has broken his oath, because oaths are governed by intention.
An example of this is when a person says, “By Allah, I shall eat this loaf,” and then eats some of it. He has not broken his oath unless he intended only a portion of it—that is, unless his aim was merely to taste it. The same applies where there is an indicating circumstance, as discussed earlier regarding one who swore to drink the water of a river. Thus, if there is an intention indicating that he meant only part of it, or a contextual indication showing that he meant only part of it, that is acted upon.