St. Symeon the New Theologian ca. 949-1022
Baptism does not take away our free will or freedom of choice, but gives us the freedom no longer to be tyrannized by the devil unless we choose to be. After baptism it is in our power either to persist willingly in the practice of the commandments of Christ, into whom we were baptized, and to advance in the path of His ordinances, or to deviate from this straight way and to fall again into the hands of our enemy, the devil.
Whoever after baptism deliberately submits to the will of the devil and carries out his wishes, estranges himself – to adapt David’s words – from the holy womb of baptism (cf. Ps. 58:3). None of us can be estranged or alienated from the nature with which we are created. We are created good by God – for God creates nothing evil – and we remain unchanging in our nature and essence as created. But we do what we choose and want, whether good or bad, of our own free will. Just as a knife does not change its nature, but remains iron whether used for good or for evil, so we, as has been said, act and do what we want without departing from our own nature. (One Hundred and Fifty Three Practical and Theological Texts 109-110)