The Bible says there’s only one unforgivable sin and that’s blasphemy against the Holy Spirit; but what does that look/sound like you may say.
Well, in Matthew (12:22-37), Mark (3:23-27), and Luke (11:17-22), Jesus explains…
Then they brought him a demon-possessed man who was blind and mute, and Jesus healed him, so that he could both talk and see. All the people were astonished and said, “Could this be the Son of David?” But when the Pharisees heard this, they said, “It is only by Beelzebub, the prince of demons, that this fellow drives out demons.” Jesus knew their thoughts and said to them, “Every kingdom divided against itself will be ruined, and every city or household divided against itself will not stand. If Satan drives out Satan, he is divided against himself. How then can his kingdom stand? And if I drive out demons by Beelzebub, by whom do your people drive them out? So then, they will be your judges. But if I drive out demons by the Spirit of God, then the kingdom of God has come upon you. Or again, how can anyone enter a strong man’s house and carry off his possessions unless he first ties up the strong man? Then he can rob his house. He who is not with me is against me, and he who does not gather with me scatters. And so I tell you, every sin and blasphemy will be forgiven men, but the 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, neither in this age or in the age to come. Make a tree good and its fruit will be good, or make a tree bad and its fruit will be bad, for a tree is recognized by its fruit. (Matthew 12:22-33)
Why was Jesus explaining that a kingdom divided against itself will not stand? Because the Pharisees were telling people that the authority Jesus had to bind and drive out demons was from Satan himself. First of all, Jesus wanted to remind them that a house divided against itself will not last; if Satan is fighting with his demons how does he get anything accomplished? And secondly, good things are not in Satan’s nature; Jesus says “make a tree good and its fruit will be good, or make a tree bad and its fruit will be bad, for a tree is recognized by its fruit.”
The Pharisees refused to acknowledge that Jesus’ authority was from God, because they didn’t want to accept that Jesus was the foretold Messiah; they refused to accept that “the kingdom of God” had come upon them. Instead, they accused Jesus–and the Holy Spirit, at work within Jesus–of not being from God. Jesus stated that “blasphemy against the Spirit will not be forgiven,” because they were trying to say that the things Jesus was doing–forgiving, healing, driving out demons, and restoring life to the dead(!)–were not of God/Holy Spirit.
Today, there are many people and churches out there claiming to do all sorts of things in the name of the God/Holy Spirit/Jesus. Not all of them are true, but neither are they all false. When we see or hear things going on around us, we must put aside our flesh and listen and observe with spiritual eyes and ears; allowing the Holy Spirit to speak to us and reveal what is going on. People often state, “God is not a god of chaos,” which I assume they’re getting from Isaiah 45:18, however, not everybody worships in the same way; and what seems like chaos to us may be heavenly harmony to God.
In conclusion, don’t be so quick to judge what is/isn’t of God. We must put aside what our flesh tells us–and sometimes what others have told us–and instead, listen to the guiding voice of the Holy Spirit, and compare everything to the truth found in God’s Word (which means studying God’s Word for yourself); and remember, His Word tells us that a tree is recognized by its fruit…therefore, always ask “what kind of fruit is being produced?”