Knowing the truth is critical.
Can you tell the real thing from the fake? 
The Pharisees thought Jesus was a counterfeit, a pretender…. 
Jesus asked His disciples 
“…Who do men say that I, the Son of Man, am?” So they said, “Some say John the Baptist, some Elijah, and others Jeremiah or one of the prophets.” He said to them, “But who do you say that I am?” Simon Peter answered and said, “You are the Christ, the Son of the living God.” Jesus answered and said to him, “Blessed are you, Simon Bar-Jonah, for flesh and blood has not revealed this to you, but My Father who is in heaven.”‭‭Matthew‬ ‭16:13-17‬ ‭NKJV‬‬
The only way to see the truth when it is standing before you is to have the truth revealed to you from Holy Spirit, the spirit of truth. 
Beware…. Jesus said many will come in my name… do not be deceived… (Mathew 24:5)