'Slaying' in the Bible

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.'

But if the sun has risen, there will be bloodguilt for him. The thief [if he lives] must make [full] restitution; if he has nothing, then he shall be sold [as a slave to make restitution] for his theft.