John Trapp on Hebrews 6:8

Verſe 8. Is rejected, and is nigh to curſing] the ſin againſt the holy Ghoſt is therefore unpardonable, becauſe God (not ſuffering himſelf to be derided, or his Spirit of truth to be found a liar) ſmiteth theſe ſinners againſt their own ſouls, with blindeneſſe and reprobacy of minde, whence follows. 1. An impoſſibility of repentance, ſith it is the work of that spirit whom they have deſpited and will not ſuffer any ſaving operation of his to faſten on their ſouls. 2. Such a deſperate fury invadeth them, that they reſiſt and repudiate the matter of remiſſion, the bloud of Chriſt, thereby if they might have mercy, yet they would not; but continue raying and raging againſt both the phyſick and the phyſitian, to their endleſſe ruth and ruine.