“And everyone who speaks a word against the Son of Man will be forgiven, but the one who blasphemes against the Holy Spirit will not be forgiven” (Luke 12:10, ESV).
The context in which this thought is found is significantly different than the context of Matthew 12:32 and Mark 3:29. One could loosely paraphrase Jesus’ words in this context as follows: “Due to the upcoming persecution, there will be times in which you will be tempted to forsake Me and even blaspheme Me by denying My name. To do such would be to sin, but such can be forgiven, if you repent. However, if you continue to deny Me and grow hard-hearted, like the Pharisees, you will eventually come to a point where repentance is impossible (and consequently, so is forgiveness).”