Thirsting Souls Bible Teaching

(Heb 6:4) “For [it is] impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost, (5) And have tasted the good word of God, and the powers of the world to come, (6)  If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame.”  Part One: in every area of instruction/learning, it is built upon basics. One never throws out a basic, but instead builds upon it. In other words, I never throw away what I know in the face of what I don’t know. These verses are such an example. They seem to say something contrary to the myriad verses that teach salvation cannot be lost.