God moved about in human form

Inasmuch as ye yourselves have now come to the belief that God moved about in the form and all other circumstances of man’s nature, you will of course no longer require to be convinced that God conformed Himself to humanity, but feel yourselves bound by your own faith. For if the God (in whom ye believe,) even from His higher condition, prostrated the supreme dignity of His majesty to such a lowliness as to undergo death, even the death of the cross, why can you not suppose that some humiliations are becoming to our God also, only more tolerable than Jewish contumelies, and crosses, and sepulchres?

Tertullian
The Five Books Against Marcion, Book II
Chapter XXVII

Christians believe God became man and died

We who believe that God really lived on earth, and took upon Him the low estate of human form, for the purpose of man’s salvation, are very far from thinking as those do who refuse to believe that God cares for anything.

…Fortunately, however, it is a part of the creed of Christians even to believe that God did die, and yet that He is alive for evermore.

Tertullian
The Five Books Against Marcion, Book II
Chapter XVI

Christ’s substance is both man and God

Christ Jesus our Lord (may He bear with me a moment in thus expressing myself!), whosoever He is, of what God soever He is the Son, of what substance soever He is man and God, of what faith soever He is the teacher, of what reward soever He is the Promiser, did, whilst He lived on earth, Himself declare what He was, what He had been, what the Father’s will was which He was administering, what the duty of man was which He was prescribing; (and this declaration He made,) either openly to the people, or privately to His disciples, of whom He had chosen the twelve chief ones to be at His side, and whom He destined to be the teachers of the nations.

Tertullian
Against Marcion
The Prescription Against Heretics
Chapter XX

The Word is God in man and man God

But that man with whom the Word dwells does not alter himself, does not get himself up: he has the form which is of the Word; he is made like to God; he is beautiful; he does not ornament himself: his is beauty, the true beauty, for it is God; and that man becomes God, since God so wills. Heraclitus, then, rightly said, “Men are gods, and gods are men.” For the Word Himself is the manifest mystery: God in man, and man God. And the Mediator executes the Father’s will; for the Mediator is the Word, who is common to both—the Son of God, the Savior of men; His Servant, our Teacher. And the flesh being a slave, as Paul testifies, how can one with any reason adorn the handmaid like a pimp? For that which is of flesh has the form of a servant. Paul says, speaking of the Lord, “Because He emptied Himself, taking the form of a servant,” calling the outward man servant, previous to the Lord becoming a servant and wearing flesh. But the compassionate God Himself set the flesh free, and releasing it from destruction, and from bitter and deadly bondage, endowed it with incorruptibility, arraying the flesh in this,

Clement of Alexandria
The Paedagogus, Book III
Chapter I

God in the form of man and is God

Now, O you, my children, our Instructor is like His Father God, whose son He is, sinless, blameless, and with a soul devoid of passion; God in the form of man, stainless, the minister of His Father’s will, the Word who is God, who is in the Father, who is at the Father’s right hand, and with the form of God is God.

Clement of Alexandria
The Paedagogus, Book I
Chapter II

Jesus is most manifest Deity and equal to God

For it was not without divine care that so great a work was accomplished in so brief a space by the Lord, who, though despised as to appearance, was in reality adored, the expiator of sin, the Savior, the clement, the Divine Word, He that is truly most manifest Deity, He that is made equal to the Lord of the universe; because He was His Son, and the Word was in God, not disbelieved in by all when He was first preached, nor altogether unknown when, assuming the character of man, and fashioning Himself in flesh, He enacted the drama of human salvation: for He was a true champion and a fellow-champion with the creature.

Clement of Alexandria
Exhortation to the Heathen
Chapter X

God exerted Himself in Christ to save us

He awed men by the fire when He made flame to burst from the pillar of cloud—a token at once of grace and fear: if you obey, there is the light; if you disobey, there is the fire; but since humanity is nobler than the pillar or the bush, after them the prophets uttered their voice,—the Lord Himself speaking in Isaiah, in Elias,—speaking Himself by the mouth of the prophets. But if thou dost not believe the prophets, but supposest both the men and the fire a myth, the Lord Himself shall speak to thee, “who, being in the form of God, thought it not robbery to be equal with God, but humbled Himself,” He, the merciful God, exerting Himself to save man. And now the Word Himself clearly speaks to thee, shaming thy unbelief; yea, I say, the Word of God became man, that thou mayest learn from man how man may become God.

Clement of Alexandria
Exhortation to the Heathen
Chapter I

The Word who appeared to man is both God and man

Well, inasmuch as the Word was from the first, He was and is the divine source of all things; but inasmuch as He has now assumed the name Christ, consecrated of old, and worthy of power, he has been called by me the New Song. This Word, then, the Christ, the cause of both our being at first (for He was in God) and of our well-being, this very Word has now appeared as man, He alone being both, both God and man—the Author of all blessings to us; by whom we, being taught to live well, are sent on our way to life eternal.

Clement of Alexandria
Exhortation to the Heathen
Chapter I