If one was merciful, what would he do?
Malbim: He would not allow [others] to destroy you.
What is the meaning of "Mi Yanud"?
Rashi: Who will lament?
Radak, Malbim: Who will console you?
What is the meaning of "u'Mi Yasur"?
Rashi: Who will turn from his path to you, to greet you? Malbim - people who are close come to console during the Aveilus. [Normally,] even far people come to give Shalom, also after the Aveilus.
Radak: It is consoling a mourner, like "Lanud Lo u'Lenachamo" (Iyov 2:11), and to recount the afflictions with him. This expression is used, for consolers stray from their places - this one from here and this one from here, to console the mourner. Who will have mercy, who will console you, who will turn to greet you? You caused your destruction, for you abandoned Me! Therefore, you will go in back, and not in front.
