What is sin?
God will forgive us all of our sins but one, and that is to both believe in
God without a doubt, and to understand his word, and yet to speak or work
against God or his word. For this you are in danger of the second death in the
lake of fire. Once you have received the holy spirit into your life you
are no longer part of this world, but only living in it. To return to the
world is to turn your back on God and to choose Satan, you are no longer
deceived by Satan but accept him as your God. The Holy Ghost is of God, and is
God. This saying can be hard to understand, yet Gods ways are not our ways, and
nothing is impossible when it comes to God. The holy Ghost or holy spirit is a
force generated from God to help open your mind up, to guide, and protect, and
strengthen us from the evil around us.
But what will not be forgiven? Knowing and willingly rejecting/neglecting the Holy Spirit which is received after repentance and baptism.
Once you are enlightened with Gods spirit and with the knowledge of God, you can not easily turn your back on God and then think you can come back to God again, believing he will accept you back.