Are there any sins which are unforgivable? Why are they called "unforgivable sins"?
"'He who is not with me is against me, and he who does not gather with me scatters. Therefore I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven. And whoever says a word against the Son of man will be forgiven; but whoever speaks against the Holy Spirit will not be forgiven, either in this age or in the age to come" (Matthew 12:22-32). This basically means if you don't believe in God so you are not even asking forgiveness. Your heart is hardened and you stubbornly hold on to your unbelief. God cannot forgive a sin you don't repent of.