Tertullian († c. 222) is the greatest Latin apologist, and the pioneer of Western theology. Following the second-century Church Fathers, he vigorously proclaimed the primitive core of the faith on which rests the whole work of Salvation: Mary’s virginal conception and true motherhood.
Mary’s motherhood is a true one in the precise sense that Christ was truly a man, he really took his body in her, his flesh was true human flesh. By this real way of being a man, the Son of God, through Mary, summarized in himself all the heritage of the patriarchs, the promises of God to Israel, and he also united himself to the first man of whom he became the son and the Savior:
“Tell me this, please: if God’s Spirit came down in a womb without intending to take flesh in it, why come down in a womb? He could have stayed outside of it and taken on a spiritual flesh.” 
“What sort of flesh can we and must we recognize in Christ? Assuredly no other flesh than Abraham’s, since Christ is Abraham’s seed; no other flesh than Jesse’s, since Christ is the flower of Jesse’s shoot; no other flesh than David’s, since Christ is the fruit of David’s loins; no other flesh than Mary’s, since Christ is from Mary’s womb; finally, to go back even further, no other flesh than Adam’s, since Christ is the second Adam.”.
Mary’s motherhood is a true one, but it is virginal too: Christ’s Father is God and his mother is a virgin:
“It wasn’t fitting for the Son of God to be born of a human seed, for fear that being entirely son of man, he would not have been equally son of God, and would have had in him nothing more than Solomon or Jonas (...)
To be son of man too, he had to take his flesh, and it only, which he had to take from man’s flesh, without man’s seed. Indeed man’s seed was superfluous for someone who had within him God’s seed. So, in the same way that before he was born of a virgin, he could have God as his father without having a human mother, by being born of the Virgin, he could have a human mother without having a human father.”
Tertullian was able to consider Mary’s virginal motherhood under its most profound aspect that ties her to the Trinitarian mystery (God the Father, the Son, and Holy Spirit). This is the merit of this great African theologian.
 Tertullien, De carne Christi 19,5 , in J-P MAHE, Tertullian, The Flesh of Christ, source chretiennes 216, Paris, Cerf, 1975, p. 289
 Tertullien, De carne Christi 22, 6, in J-P MAHE, Tertullian, The Flesh of Christ, source chretiennes 216, Paris, Cerf, 1975, p. 301
 Tertullien, De carne Christi 18, in J-P MAHE, Tertullian, The Flesh of Christ, source chretiennes 216, Paris, Cerf, 1975, p. 283-285