Faith is a gift from God
Catechism of the Catholic Church states that no one can merit the initial grace of forgiveness and justification at the beginning of our conversion (# 2010) and moved by grace we turn to towards God (#1989). In other words, faith (in Christ and in God) is a gift. When we say faith is a gift, it means it is given not because we do something to deserve it. On this issue Augustine wrote (English Translation from Nicene and Post Nicene Fathers or NPNF Series I Volume 5, available online at http://www.ccel.org):
But perhaps it may be said: “The apostle distinguishes faith from works; he says, indeed, that grace is not of works, but he does not say that it is not of faith.” This, indeed, is true. But Jesus says that faith itself also is the work of God, and commands us to work it. For the Jews said to Him, “What shall we do that we may work the work of God? Jesus answered, and said unto them, This is the work of God, that ye believe on Him whom He hath sent.” [John 6:28] The apostle, therefore, distinguishes faith from works, just as Judah is distinguished from Israel in the two kingdoms of the Hebrews, although Judah is Israel itself. And he says that a man is justified by faith and not by works, because faith itself is first given, from which may be obtained other things which are specially characterized as works, in which a man may live righteously. For he himself also says, “By grace ye are saved through faith; and this not of yourselves; but it is the gift of God,” [Ephesians 2:8] that is to say, “And in saying ‘through faith,’ even faith itself is not of yourselves, but is God’s gift.” “Not of works,” he says, “lest any man should be lifted up.” For it is often said, “He deserved to believe, because he was a good man even before he believed.” Which may be said of Cornelius [Acts 10] since his alms were accepted and his prayers heard before he had believed on Christ; and yet without some faith he neither gave alms nor prayed. For how did he call on him on whom he had not believed? But if he could have been saved without the faith of Christ the Apostle Peter would not have been sent as an architect to build him up; although, “Except the Lord build the house, they labour in vain who build it.” [Psalms 127:1] And we are told, Faith is of ourselves; other things which pertain to works of righteousness are of the Lord; as if faith did not belong to the building,-as if, I say, the foundation did not belong to the building. But if this primarily and especially belongs to it, he labours in vain who seeks to build up the faith by preaching, unless the Lord in His mercy builds it up from within. Whatever, therefore, of good works Cornelius performed, as well before he believed in Christ as when he believed and after he had believed, are all to be ascribed to God, lest, perchance any man be lifted up.
Augustine, A Treatise on the Predestination of the Saints, Book 1, Chapter 12