Jesus Speaking.

30 Whoever is not with me is against me, and whoever does not gather with me scatters. 31 Therefore I tell you, every sin and blasphemy will be forgiven people, but the blasphemy against the Spirit will not be forgiven. 32 And whoever speaks a word against the Son of Man will be forgiven, but whoever speaks against the Holy Spirit will not be forgiven, either in this age or in the age to come.

A continued state of unbelief and resistance to the Holy Spirit would prevent you from being saved.

Full and final denial. God doesn’t give us unlimited chances to submit and turn to Him when He calls and knocks. In fact eventually He gives them over to a reprobate mind, or sends upon them a strong delusion so that they would believe a lie. Why? Because they received not a love of the truth.

Once regenerated, converted, submitted, surrendered, adopted…you do have unlimited forgiveness. He is just and faithful to forgive us if we but ask in humility to wash us clean.

All your referenced scriptures in context where Paul’s letters written to other BELIEVERS.