Exodus Chapter 4, Verse 23
From BibleWiki
23: And I say unto thee, Let my son go, that he may serve me: and
if thou refuse to let him go, behold, I will slay thy son,
even thy firstborn.
23: And I said to thee, Send away my people, that they may serve me: now if thou wilt not send them away, see, I will slay thy first-born son.
If Pharaoh would not let Jehovah's first-born son depart, he would pay the penalty in the life of his own first-born (cf. Ex 12:29). In this intense earnestness of the divine command, Moses had a strong support to his faith. If Israel was Jehovah's first-born son, Jehovah could not relinquish him, but must deliver His son from the bondage of Egypt.
