Although all three Persons of the Blessed Trinity perform the work of sanctifying human souls, this work is especially attributed to the third Person, the Holy Ghost, because He is the Person who proceeds from the Father and the Son as the breathing of their love; and sanctification is a work of love. God Himself indicated this when He attributed the Incarnation, the source of all man's sanctity, to the Holy Ghost, saying to the Blessed Virgin Mary, through the message of the Angel Gabriel: "The Holy Spirit shall come upon thee" (Luke 1:35).
God sanctifies the human soul by the supernatural gift of grace. The most exalted type of grace is sanctifying grace, which is a spiritual quality, dwelling in the soul, making it like God Himself. The New Testament is filled with allusions to this grace, which is referred to as a new life, a sharing in God's life. Our Lord spoke of the reception of this life as a spiritual birth, when He said: "Unless a man be born again of water and the Spirit, he cannot enter into the kingdom of God" (John 3:5). Once it has been received, sanctifying grace remains in the soul unless it is driven out by mortal sin. And when one has received sanctifying grace, he can grow in it constantly, for it increases with every worthy reception of a sacrament, and with every supernaturally meritorious work.
Actual grace, as the name indicates, is given for the performance of a good, supernatural action. It is a direct force from God Himself. It contains an enlightenment of the mind and an inspiration of the will. We should be very careful not to neglect it, for it is a precious gift of God, and if we neglect one such grace we may deprive ourselves of a whole chain of extraordinary graces that God had planned for us. Even sinners receive actual graces, impelling them to turn again to God. Indeed, without actual grace, we cannot perform any supernaturally good action; for our natural powers are unable to rise to the supernatural plane.
God does not distribute actual graces equally to all; some persons receive much more than others. There is no injustice in this on the part of God, for grace is a free gift from Him, and He can distribute it according to His good pleasure. But all receive sufficient grace to be saved.
The chief fruit of sanctifying grace is merit a claim or right to receive an increase of sanctifying grace, together with a claim to a corresponding measure of glory and happiness in heaven. We can increase in heavenly merit indefinitely. Not only works which are by their nature good, such as prayer and the reception of the sacraments and attendance at Mass, but even the ordinary works of our day, such as the taking of our meals, study, our games and amusements, can become meritorious if we perform them under the proper conditions. These conditions are very easy - we must be in the state of grace, and offer our works to God out of love for Him. We do not have to make this offering with each work we perform. It is sufficient to make it from time to time, particularly every morning, intending to include in it all our thoughts, words and actions. Thus, it would suffice to say in our heart: "O my God, I offer Thee every deliberate action I shall perform, because I love Thee on account of Thy infinite goodness".
A person in mortal sin cannot merit any heavenly reward, even though he may perform very good deeds; but by performing good deeds from a supernatural motive he can prepare himself for repentance and for a return to the state of sanctifying grace.
RESOLUTION: Resolve out of love for God to offer Him frequently all the actions of the entire day, even the slightest.