Exodus 4:23

ASV — American Standard Version

“and I have said unto thee, Let my son go, that he may serve me; and thou hast refused to let him go: behold, I will slay thy son, thy first-born.”

KJV — King James Version

“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.”

WEB — World English Bible

“and I have said to you, “Let my son go, that he may serve me;” and you have refused to let him go. Behold, I will kill your firstborn son.’ ””