Do Names = Identity?

I hear some talk about names as though they have special power and will always call a specific deity; for example the tetragrammaton – YHVH. On the flip side I heard it said that names were not so precise; but it was rather the spirit it’s self that is recognizable (it’s actions, it’s essence, etc.) , and that a spirit could go by many names or pretend to be other spirits.

Do these views contradict each other? Would either contradict the egregore concept? And if so Which do you more closely believe?