That's exactly right Laura.

It is ok to deceive decievers, especially when their intentions toward others are not good. The hebrews even stole the egyptians jewlery to ensure they were angry enough to follow them. what better way to ensnare a rich man but to take his gold? Pharoah lost his entire army in an afternoon that way.

In essence, deceiving a deceiver nullifes the event since the event is deceitful to begin with.

God's word says that even God with help those who love deception by sending them plenty of it.