Tolstoy said:
"Faith is a knowledge of the meaning of human life, the consequences of which is that man does not kill himself, but lives. Faith is the force of life. If a man lives, then he must believe in something...Without faith it is impossible to live." (from his book A Confession )
The Hebrew word
aman is translated as “believe”, “trust”, “have faith”, and also “support”, “nourish”, and “make lasting”. A derivative word is
omenat, meaning “pillars” or “supports of the door” as in
2 Kings 18:16. Another cognate is
emunah, which is “faithfulness” or “trust”, as in
Exodus 17:12 where God brought victory to Israel as long as Moses would hold his hands up. Aaron and Hur held up his hands so that they “remained
emunah until sundown”. All of these illustrate that faith is an action that we take, which is exactly what the Catholic church teaches. Faith is a work, it's about what you DO and not merely about what you believe.
We are not able to do this work by our own effort because of the effects of original sin. Each and every time we turn toward God and away from sin it is because God gave us
at that moment the grace to be able to do it. It is completely and totally due to the grace of God, who enables all of us at some point in our lives to perform the work of freely responding to Him by performing the "obedience of faith". At that moment we truly have the choice that Adam had, to submit to God or submit to ourselves, and we only have that choice because of God’s grace.
The Catechism of the Catholic Church expresses this by saying that faith is an act of the will in which one turns toward God and away from sin; in which we decide that we will cooperate, with our intellect and will, with the divine grace that God gives us to enable us to comply with the moral law; it is a free response of the human person to the initiative of God; it is a personal adherence of the whole man to the God who reveals himself. It is the theological virtue by which we believe in God and believe all that he has said and revealed to us, and that Holy Church proposes for our belief, because he is Truth itself. By faith "man freely commits his entire self to God." For this reason the believer seeks to know and do God's will. "The righteous shall live by faith." Living faith "works through charity."
These are all
actions, things we
do in obedience to God. Thus the Apostle Paul says in
Romans 1:5 "Through Him we have received the grace of apostleship, to bring about the obedience of faith...”
This obedience is the essence of Christianity: submission to the Eternal One who was enfleshed, and through that submission being brought into union with Him so that we may participate in His divine life.