We are not justified by our wisdom, intelligence, piety, or by any action of ours, however holy, but by faith, the one means by which God has justified us from the beginning. To him be glory forever and ever.
What must we do then? Give up good works? Stop practicing Christian love? God forbid! We must be ready and eager for every opportunity to do good, to put our whole heart into it. Even the Creator and Lord of the universe rejoices in his works. [If God rejoices in his works] this should inspire us with a resolute determination to do [God’s] will and make us pour our whole strength into the work of living a Christian life.
—Clement of Rome, First Letter to the Corinthians 31-33
A wonderful example of what the good saint talks about here.
If I pray before I play0 music, I can put my whole heart into it easily. If I forget to pray, then I am not putting my whole heart into it.