NASB 1995
"So I said to you, 'Let My son go that he may serve Me'; but you have refused to let him go. Behold, I will kill your son, your firstborn."'"

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.

Berean Study Bible
and I told you to let My son go so that he may worship Me. But since you have refused to let him go, behold, I will kill your firstborn son!’ ”

Douay-Rheims Bible
I have said to thee: Let my son go, that he may serve me, and thou wouldst not let him go: behold I will kill thy son, thy firstborn.

English Revised 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 firstborn.

King James Bible
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.

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 son, your firstborn.'"

Young's Literal Translation
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.'

Exodus 4:23 Additional Translations ...