Exodus 4:21-24

²¹ And Jehovah saith unto Moses, 'In thy going to turn back to Egypt, see—all the wonders which I have put in thy hand—that thou hast done them before Pharaoh, and I—I strengthen his heart, and he doth not send the people away; ²² and thou hast said unto Pharaoh, Thus said Jehovah, My son, My first-born 'is' Israel, ²³ and I say unto thee, Send away My son, and he doth serve Me; and—thou dost refuse to send him away—lo, I am slaying thy son, thy first-born.'

²⁴ And it cometh to pass in the way, in a lodging place, that Jehovah meeteth him, and seeketh to put him to death;