Upvote:2
Blasphemy against The Holy Spirit is not something you would do unknowingly or mistakenly. To blaspheme against The Holy Spirit you must know that He exists, as did the Apostles. Being saved isn't the bar for this it is a knowledge much greater than that it is to know as if you had seen it with your own eyes.
It would be like Cain who lied to God and knew he was God, you must commit the sin with full knowledge of what you are doing and you do it on purpose with your own agency.