Yes, Jesus is the man...

Jesus was fully man and fully God: at birth; at baptism; at death:

1 John 5:5-12
"This is the One who came by water and blood, Jesus Christ, not with water only, but with the water and with the blood. And it is the Spirit that bears witness because the Spirit is the truth, for there are three that bear witness, the Spirit, and the water, and the blood, and the three are in agreement. If we receive the witness of men, the witness of God is greater, for the witness of God is this, that He has borne witness concerning His Son. The one who believes in the Son of God has the witness in himself. The one who does not believe God has made Him a liar because he has not believed in the witness that God has borne concerning His Son. And the witness is this, that God has given us eternal life and this life is in His Son. He who has the Son has the life; he who does not have the Son of God does not have the life."

There is a group of people that claim to be the witnesses of God, they even call themselves Jehovah's Witnesses. And they claim to be propagating the truth that God wants revealed. They claim to be echoing the witnesses of God. But the truth that God once revealed, the true witness of God is that Jesus is the Christ, the Son of God, God incarnate. And the so-called Jehovah's Witnesses are liars because they deny the very thing to which God gives in the New Testament, summed up in the text I just read. The Jehovah's Witness religious movement says that Jesus may be called "a" god, small "g," but not THE God.

They say He is mighty but not the Almighty.
They say He was created by Jehovah, He is not a member of the Trinity, there is no Trinity.
Elohim, which is a plural word, means plural in majesty, not in person.
They say that the Son during His pre-human state was really an angel by the name of Michael.
They further say that the Son did not even possess immortality. He was created and created to die.
They teach that when Christ was born of Mary, He ceased being a spirit person all together and became nothing more than a human being. The Jesus that walked on earth had only one nature and that was the nature of a man. He was a perfect man, the
equivalent of Adam before the Fall.
The Jehovah's Witnesses also teach that Jesus became, or took on, the role of Messiah when He was baptized.
It was there that God made this human being His spiritual Son. And so He was first a created angel, then a created man, and finally the spiritual Son.
The Jehovah's Witnesses deny that Jesus physically, literally arose from the dead. He was not raised as a human son, He was only raised as an immortal spirit, His body never came back to life. In fact, once He had sacrificed His body, they say, He could never get it back.
Judge Rutherford, the demon-inspired man who invented the religion of Jehovah's Witnesses, said that the body of Jesus was disposed of and God who knows where it is will bring it back and put it on exhibit in some millennial museum.
They say Christ once a mortal angel, then a mortal man, and finally an immortal spirit will live on forever as a spirit being.

And from the way their writings are understood, has regained the original name of Michael. He is back enjoying angelic life.
Well you can see from this mish-mash that these people are not Jehovah's witnesses.
They are not witnesses of the true God.
They do not echo God's witness.
They do not echo God's testimony concerning His Son.
They are liars and they are representatives of the father of lies, they are the devil's witnesses.

And they have many old heresies reframed in their system, very old heresies that come from ancient Gnosticism. This kind of stuff lies behind what John says. This is part of the developing of Gnosticism. We've seen how they believe that spirit was good and matter was evil, and so they denied the full doctrine of the incarnation that God, the good Spirit, could ever take up permanent residence in a human being, was unacceptable to the dualism of their thinking. They did allow the Christ's Spirit to come down at the baptism, stay awhile and then go away. They could not involve God in flesh in any permanent way and certainly not in the sufferings of death.

They thought that at the baptism this divine Christ descended, came into the man Jesus who was simply human...this is part of what the Jehovah's Witnesses say today...they think that the Christ's Spirit came into Him in the imagery of the dove and then for a few years Jesus brought the message of God to man. And then the Christ's Spirit departed and only the man was crucified.

So deity, whatever form of deity it was, what ever form of Spirit being it was, left Him before the cross. And so His death on the cross was not a God/Man death, it was not a death that atoned for our sins at all. It was just another man dying another death. And the best we can draw out of Jesus is from His baptism until His Christ's Spirit left Him to follow the ethical teachings that He gave us.

They destroy because they despise the efficacious substitutionary atonement of Jesus Christ. Any heresy, any heresy that tampers with the death of Christ, the blood of Christ as God bearing the sins of men is satanic. John points that out in chapter 2 of this epistle. "He Himself, Jesus Christ the righteous, is the propitiation for our sins and not for ours only but also for those of the whole world." And then again as I read earlier in 4:10, "He sent His Son to be the propitiation for our sins."

He came not just to teach us good things and then die as another man, He came to offer Himself as an atoning sacrifice, satisfying God for us. And so, John says this one who came, Jesus Christ, was simultaneously from His birth to His death and forevermore the man Jesus and God. Syrinthis(???) who came up with this, I guess, originally and his followers are dead. Their creed is no factor today. But all who deny the incarnation, all who deny the substitutionary death of Jesus Christ whether totally or partially, all who pervert that great truth are heretics undermining the basis of our salvation. If Christ did not take His divine nature to the cross, He cannot reconcile us to God. If He wasn't fully God He could not and did not conquer sin or death for us. "But He who knew no sin became sin for us that we might become the righteousness of God in Him."

Some help from Pastor John MacArthur helps in clarifying God's Witness of His Son, Jesus Christ.