What if you have a thought against the holy ghost come into your mind and don't say it out loud. Are you then damned forever? That could happen to anyone?
Yes, we know who you are. No, even if you utter blasphemies out loud against the Holy Spirit, that is not what is unforgiveable. Just think about it for a moment. In the Scripture passage, did the Pharisees themselves ever blaspheme the Holy Spirit directly, by name, out loud. What did they do? They attributed the works of Our Lord to the devil. Our Lord did what He did in order to establish His credibility as God, which credibility is then what leads to supernatural faith. So the resistance to recognizing God's work in Our Lord is what was referred to as blasphemy against the Holy Spirit. Refusing to recognize God as having revealed in Christ is THE obstacle to supernatural faith and to salvation.