KJV - 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.
ASV - 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.
BBE - And I said to you, Let my son go, so that he may give me worship; and you did not let him go: so now I will put the first of your sons to death.
WEB - 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.'"
YLT - 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.'