The Requirement of Verbalizing the Oath of Abstention and Specifying the Duration

Question:
Honorable Shaykh, does the oath of abstention (ila') require the husband to verbalize it by specifying a duration, or not?

Answer:
It requires verbalization, meaning my intention is verbalization with the night, or rather, my intention is verbalization with a duration. Verbalization with the night is necessary; the oath is not established except through verbalization. As for if he intends it in his heart, nothing results from that. If he divorces in his heart, if he swears an oath in his heart, nothing results from that until he verbalizes it. However, if his intention is that he did not mention a duration, if he swore an oath of abstention from his wife and did not mention a duration, then four months are set for him; a duration of four months appears for him. If he returns during that time, otherwise, when the four months are completed, it becomes apparent, like if he specified, for example...