For he supposed his brethren would have understood... — Better, and he supposed. The Greek conjunction never has the meaning of “for,” and the insertion of that word gives to the act of slaying the Egyptian a deliberate character which, in the narrative of Exodus 2:11-12, does not belong to it.
Would deliver them. — Literally, was giving them salvation, or deliverance; the act being itself one of championship and the first step to deliverance.