Exodus 4:23
“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.”
And the Lord said unto Moses, When thou goest to return into Egypt, see that thou do all those wonders before Pharaoh, which I have put in thine hand: but I will harden his heart, that he shall not let the people go.
And thou shalt say unto Pharaoh, Thus saith the Lord, Israel is my son, even my firstborn:
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.
And it came to pass by the way in the inn, that the Lord met him, and sought to kill him.
Then Zipporah took a sharp stone, and cut off the foreskin of her son, and cast it at his feet, and said, Surely a bloody husband art thou to me.
Why This Verse Was Tagged
This verse was identified through meaning similarity — its content is mathematically close to known verses in this theme, even without sharing the same vocabulary.
Counter-Arguments
The strongest case that this verse does not belong in this theme.

Related Verses
“And thou shalt say unto Pharaoh, Thus saith the Lord, Israel is my son, even my firstborn:”
“Then the Lord said unto Moses, Go in unto Pharaoh, and tell him, Thus saith the Lord God of the Hebrews, Let my people go, that they may serve me.”
“And the Lord said unto Moses, Rise up early in the morning, and stand before Pharaoh, and say unto him, Thus saith the Lord God of the Hebrews, Let my people go, that they may serve me.”
“And Pharaoh called unto Moses, and said, Go ye, serve the Lord; only let your flocks and your herds be stayed: let your little ones also go with you.”
“And the Lord spake unto Moses, Go unto Pharaoh, and say unto him, Thus saith the Lord, Let my people go, that they may serve me.”