2 John 9 New American Standard Bible
9 Anyone who goes too far and does not remain in the teaching of Christ, does not have God; the one who remains in the teaching has both the Father and the Son.
The ability to remain in right relationship with God has everything to do with remaining in the teaching of Christ and who He claims to be. If we begin to doubt that Jesus is God because of false teaching and deception, we can run into real danger of walking away from Christ.
Jesus compared us to sheep. Sheep are not very intelligent animals and truly need a shepherd for protection and survival. A sheep left to their own devices will wander off and put themselves in life threatening situations. If we fail to guard our hearts against false teaching and we give it any opportunity to impact our hearts and minds, it can have destructive consequences.
The greatest place of protection is abiding in Christ. It is daily abiding in the truth and renewing our minds by the word of God. Our world is filled with deception and darkness because Satan is the god of this age. He has blinded the hearts and minds of people. Daily we must pursue to know Christ in greater ways and to hold firmly to the truth.
If we abide in the truth, we will not only have relationship with Jesus, but we will also be in right relationship with the Father. Salvation begins with a decision to follow Jesus, but daily we must remain and abide in Christ. As we abide and remain in the truth the very life of Christ is produced within us.