According to the Bible, what sin can never be forgiven, and why?

 

According to the Bible, the sin that is often referred to as unforgivable or the "unpardonable sin" is blasphemy against the Holy Spirit. This concept is found in several passages, including Matthew 12:31-32, Mark 3:28-30, and Luke 12:10. In Matthew 12:31-32 (New International Version), Jesus says:

"And so I tell you, every kind of sin and slander can be forgiven, but blasphemy against the Spirit will not be forgiven. Anyone who speaks a word against the Son of Man will be forgiven, but anyone who speaks against the Holy Spirit will not be forgiven, either in this age or in the age to come."

The reason why blasphemy against the Holy Spirit is considered unforgivable is a matter of interpretation and theological debate. However, many scholars and theologians interpret it as a persistent and deliberate rejection of the work of the Holy Spirit, which ultimately leads to a state of spiritual hardness or unrepentance. Essentially, it is a rejection of God's forgiveness and grace, which renders one incapable of receiving forgiveness.

It's important to note that interpretations of this passage may vary among different Christian denominations and theological traditions. Some hold that this sin is a specific act of attributing the work of the Holy Spirit to Satan, while others understand it as a broader concept of persistent rejection of God's grace.