By this you know the Spirit of God: every spirit that confesses that Jesus Christ has come in the flesh is from God;1 John 4:2(NASB)
Christendom is saturated with heretical and apostate teachings. The heretic believes but distorts God's Word and strays from the truth of scripture while the unbelieving apostate puts-on a garment of pretence with the subtle, but deliberate intent, to lead Christians astray. Both exemplify a ploy of the enemy to prevent genuine believers from entering into spiritual maturity and the fullness of Christ.
The apostle John tells us how a false teacher can be identified. If someone denies either the deity of Christ or His humanity, that man is a fraudulent teacher. We are not to be gullible in our Christian walk. We are to discern the spirit that is behind a teacher or his doctrine. "Dear friends", John reminds us, "do not believe every spirit. You are to test the spirits to determine if they are from God."
We are reminded, in earlier verses, that there are many spirits in the world that are not to be trusted, and the apostle points out the importance of testing every spirit to see if it is from God or if it has been spawned from the evil one. We are told that many false prophets and false teachers have gone out into the world with the deliberate intention of misleading Christians by teaching a false gospel... under the pretence of being a true believer.
From the time of John, there have been teachers and religious groups that refuse to accept that Jesus is fully God or that He is fully Man. But Jesus is both fully God and fully human. Some like to suggest that the Lord Jesus was a lesser god - a created being, while others have taught that Jesus was not fully human.. but simply the mirage of a man. However, only the perfect God is good enough to pay the price for sin and only a sinless Man could die on the cross and shed His life-blood as payment for humanities sin. It is only in the hypostatic union of Christ's humanity with His divinity, that qualified Him to be our Substitute for sin
It is ONLY faith in the incarnate Son of God - the eternal God made in human flesh, that is sufficient to pay for the price of sin and save us from death and hell. Without faith in the humanity of Christ, there is no Christian faith. Without the death, burial, and resurrection of the Lord Jesus Christ there is no forgiveness of sin and without trusting in His death, burial, and resurrection to save... we remain dead in our sin and without hope in the world.
But through the pen of John, the beloved disciple, the Holy Spirit gives a simple rule to identify, whether or not, a professing believer has the Spirit of God. John gives clear guidelines to discern whether or not a doctrine is really from the Lord. He tells us that every spirit that confesses that Jesus Christ is come in the flesh has the truth... for every person; every preacher; every teacher; every denomination; every doctrine: every spirit that does not acknowledge the humanity, of God-incarnate in the Person of the Lord Jesus Christ, proclaims a false gospel and is influenced by a 'spirit' other than the Holy Spirit of God.
It was only by the eternal God becoming a Man, that He could die as a Man as payment for the sin of mankind. It was only because the eternally existing Son of God set aside His glory, for a time, and took upon Himself humanity, that sin and death could be defeated. Life is in the blood and only the shed blood of a perfect Man was sufficient to pay the price of sin. Only the God-Man could die for us and be resurrected to life - so that in HIM we might be forgiven through his blood and receive His life.
Jesus took on humanity that He might die. He gave His life for us that we might have His life forever. Jesus eternally existed as God... but at a point in time He stepped onto the earth, and took on Himself the form of a Man. In so doing, our Saviour did not strip Him of His eternal deity. He simply set aside His glory for a time, so that He would live His life as all men ought to live.. in total submission to the Father.
We do well to reflect on this truth, for scripture tells us that as the Church age comes to a close, apostasy; heresy; the doctrines of demons and all manner of false 'gospels' will infiltrate every sector of Christianity.
Let us hold fast to the truth and confess Christ crucified, as the anointed Messiah of God and Redeemer of the world - for our Saviour Jesus Christ is Prophet; Priest and King. He is Son of God and Son of Man. He is very God of very God - incarnate and not created. He is the Word that became flesh. He is the unique God-Man, Who alone is our kinsman-Redeemer; our Lord and our God.
Dear heavenly Father, thank You that You sent the lovely Lord Jesus to be born in the flesh so that He could die for my sin. Thank You that He was willing to be born into the human race and shed His life-blood so that we might live in Him. Give me the wisdom and insight to discern the truth and not to be led astray by apostate teachers or heretics. May I feed on You in my heart by faith with thanksgiving and praise. Protect my mind from all false teachings and may I grow in grace and in a knowledge of the Lord Jesus Christ, in Whose name I pray, AMEN.