1god or 3 gods?!

[hoseintabar]

Hi every body
I have e story about Christianity
One day i was in holy shrine of hazrat e masoume
One person who was from canaidia came here he was as Christianity
I asked him what do you satisfy that god is one and on that time he is as a 3 guys
He said we accept that god is one and he is as a creator but he appeared in 3 guys
But i don’t understood what it means ?!!
. It is illegal