Jesus tells us to be as harmless as doves and shrewd as snakes.
We must be careful to discern this kind of situations.
A satanist is so much easier to identify compared to a person who
claims to bear the light of Christ and their lives speak nothing
about God at all. Jesus says "Not
everyone who says to me, 'Lord, Lord,' will enter the kingdom of
heaven, but only he who does the will of my Father who is in
heaven. (Mat 7:21 NIV) He will say to them "Then I will tell them plainly, 'I never knew you.
Away from me, you evildoers!' (Mat 7:23 NIV)".
God also says "In the same way, let your
light shine before men, that they may see your good deeds and
praise your Father in heaven. " (Mat 5:16 NIV)and
"If you love me, you will obey what I
command. (John 14:15 NIV). So he doesn't really love God
genuinely by doing that. He needs God's love to change him. So
anyone who claims that he loves God but yet refuses to obey him
doesn't really love Him at all. Our love for Him must be propelled
by a genuine encounter with God a transformation of our life when
we are a new creation in Him. I pray that God will somehow touch
him personally.