On the one hand:
"One cannot provoke, one cannot insult other people's faith, one cannot make fun of faith. There is a limit. Every religion has its dignity." -- Pope Francis
On the other hand:
"He who sits in the heavens laughs; the Lord holds them in derision" (Psalm 2:4, ESV).
"All who fashion idols are nothing, and the things they delight in do not profit. Their witnesses neither see nor know, that they may be put to shame. Who fashions a god or casts an idol that is profitable for nothing? Behold, all his companions shall be put to shame, and the craftsmen are only human. Let them all assemble, let them stand forth. They shall be terrified; they shall be put to shame together" (Isaiah 44:9-11, ESV).
"If anyone comes to you and does not bring this teaching, do not receive him into your house or give him any greeting, for whoever greets him takes part in his wicked works" (2 John 1:10-11, ESV).
"But even if we or an angel from heaven should preach to you a gospel contrary to the one we preached to you, let him be accursed" (Galatians 1:8, ESV).
"But false prophets also arose among the people, just as there will be false teachers among you, who will secretly bring in destructive heresies, even denying the Master who bought them, bringing upon themselves swift destruction" (2 Peter 2:1, ESV).