1Ti 4:1 Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils;
1Ti 4:2 Speaking lies in hypocrisy; having their conscience seared with a hot iron;
1Ti 4:3 Forbidding to marry, and commanding to abstain from meats, which God hath created to be received with thanksgiving of them which believe and know the truth.
1Ti 4:4 For every creature of God is good, and nothing to be refused, if it be received with thanksgiving:
1Ti 4:5 For it is sanctified by the word of God and prayer.
These people departed from the faith,not departed from the Bible,but departed from the truth of it,to look at Jesus as a good spiritual teacher,and not as Lord and Savior,so although they still claim the Bible,they still deny Christ,His truth,and is the doctrines of devils,so it does not sound good.
Rom 11:20 Well; because of unbelief they were broken off, and thou standest by faith. Be not highminded, but fear:
Rom 11:21 For if God spared not the natural branches, take heed lest he also spare not thee.
Rom 11:22 Behold therefore the goodness and severity of God: on them which fell, severity; but toward thee, goodness, if thou continue in his goodness: otherwise thou also shalt be cut off.
These people did not deny Jesus,they only would not allow the Spirit to lead them,so God said they would be cut off,which it is talking of people being saved,for God said for them to continue in His goodness,but they did not,which Jesus said if any person putting their hand to the plow,looks back,is not fit for the kingdom of God.
I know some people think we cannot fall away,but the Bible says otherwise.
Just allow the Spirit to lead you,and you are alright,and cannot fall away.