Eternal sin
In Catholic teaching there are six sins that blaspheme against the Holy Spirit. They are: Several passages in the Bible are frequently interpreted as referring to the unforgivable sin:
Christianity and Judaism
In Christianity, forgiveness by God is promised to the repentant even though the wronged party has not forgiven the offender: "If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness." (1 John 1:9 ) Jesus, however, requires his disciples to forgive others if they want to be forgiven themselves. Matthew 6:14,15, which follows the Lord's Prayer, says "For if you forgive men when they sin against you, your heavenly Father will also forgive you. But if you do not forgive men their sins, your Father will not forgive your sins." Forgiveness is not an option to a Christian, rather one must forgive to be a Christian.