Humankind
By "soul" the ancients meant that which gives life to the body, i.e. animals and plants have souls, but they held that it is divine in a way that the body is not. Some held that the soul is immortal. But Christians said the soul was a creature and not divine; the soul could not be immortal as that was confined to God. The soul survives beyond human death because God grants it life; just as God enables the resurrection of the body.
Humans are created in the image and likeness of God. Rationality, authority, freedom and virtue are confirmed in us by the Incarnation.
In the early centuries the Greek East emphasised our nearness to the divine, the Latin West our human limitation.
Theories of the soul: part of divine substance (rejected by Christians because only that which is of God can be divine)); existed before bodies (Plato (429-347 BC), Origen (185-254), rejected because an eternal soul could be misinterpreted as divine); begotten and transmitted like bodies (not wholly rejected, partly accounts for Augustine's view of 'original sin' which is associated with sexual activity); creationism (accepted, that each soul is created individually and directly by God.
Augustine and Pelagius (354-420/440): to the Greeks, sin had weakened the will but not rendered it incapable of choosing; to the West, the 'fall' was not an interruption but a real falling, our will turned to rebellion, emphasising our human helplessness without grace. Pelagius thought that this pessimistic view undercut free will to lead the holy life and he stressed the grace of creation, revelation and forgiveness; Adam's sin is not the sin of all. Augustine said children are born with sin. Pelagius said sin is an action but Augustine said it is a condition which led him to predestination. The Western church diluted Augustine with Baptism placed in the power of the Church. Baptismal grace close to Pelagius' grace of creation.
Luther and Calvin shared the view of Grace as God's mysterious gift, accepting predestination. A severe view of predestination had already been revived in Gottschalk (9th Century) and survived in Jansenius (1585-1638).
For all its dangers, Augustine's theology of predestination was expressed within a hymn of praise to god but Protestantism descended into cold systematisation and doctrinal tests.
The idea of grace as free gift is widely supported by the faithful in spite of doctrinal dispute; people understand god's role in grace and their role as creatures not being in conflict: people do good of their free will in the context of God's grace.
Synthesis: There has never been a settled view on grace and predestination but: God's grace is freely given; there is no credit for believing and, therefore, no blame for not believing; we have free will; but we cannot make these three points mutually consistent.