ציטירנדיקער פּירוש אויף מלכים א 19:15

His anointed. According to some, the prophet; others think that Cyrus is meant; either explanation is admissible; comp. The Lord hath anointed me (61:1), and Anoint Hazael to be king (1 K. 19:15).

By contrast, it was best for Elisha, who had a much softer personality than Eliyahu HaNavi (as evidenced by Melachim I 19:20-21 and Melachim II 2:21-22), to anoint Chazael (Melachim II 8:7-15). Elisha’s crying when informing Chazael of his divine destiny to punish our people (see Melachim I 19:15-18), likely softened the blow Chazael dealt to our people (Melachim II 12:18-19).

Yonah, in turn, was the perfect Navi to anoint Yeihu and inform him of his mission (see Melachim I 19:15-18) to utterly destroy the house of Achav (Melachim II 9:6-10). Accordingly, Yonah might have been indispensable as the Navi with the personality uniquely appropriate to communicate to Nineveh in the strongest terms that they will be completely wiped out if they do not immediately improve.

to the grave Said Rabbi Nehemiah: Every word that requires a “lammed” in the beginning, Scripture places a “hey” at the end, e.g. מצרימה, to Egypt (Gen. 12:10); מדברה, to the desert (I Kings 19:15). They asked him: Is it not written: May the wicked return to the grave (לשאולה)? Replied Rabbi Abba bar Zavda: To the lowest level of Sheol. What does it mean that they will return? After they emerge from Gehinnom and stand in judgment and are found guilty, they return to the lowest level of Gehinnom.