That was first espoused by Saint Augustine.
Furthermore, Deuteronomy 30:10-14 clearly states that G-d's nature is in our hearts and that following it is not beyond us:
...if you will hearken to the voice of the Lord your God, to keep His commandments and His statutes which are written in this Book of the Law; if you turn unto the Lord thy God with all your heart and with all your soul; for this commandment which I command you this day is not too hard for you neither is it too far off. It is not in heaven, that you should say, "Who shall go up for us to heaven, and bring it to us, and make us hear it, that we may do it?" Neither is it beyond the sea that you should say: "Who shall go over the sea for us, and bring it unto us, and make us to hear it that we may do it?" The word is very near to you, in your mouth and in your heart, that you may do it.
You do not have free will. By your nature, all you can do is sin. The Bible is clear about that as well. “None is righteous, no not ONE”. Regarding Deut.; yet they could NOT keep the commandments and God knew that it would be so. If man could keep the law there would be no reason for the sacrifice of Christ.