Definition for Sanctifying Grace
Sanctifying / Habitual Grace (Gratia Gratum Faciens):
1. Sanctifying grace elevates man's natural life so that he can (and does) participate in the supernatural life of God, i.e., sanctifying grace gives man a participation in the divine life of God. The phrase often used to characterize this type of grace is: grace builds upon nature. On the other hand, Actual Grace can be characterized as: helping to perfect our nature. As St. Athaneus wrote, “For the Son of God became man so that we might become God. [St. Athanasius, De inc. 54, 3: PG 25, 192B].” Hardon tells us, “If we are regenerated, this implies we have received a new principle of life, for as generation means the communication of nature from one person to another, so rebirth, by definition, signifies that a new principium vitae has been received, whose nature is in the same order of reality as the generator, who in this case is God.”
2. Sanctifying grace is a direct communication of God in which supernatural life is permanently (as opposed to transiently) infused into, and inheres in, the spiritual soul of man. Permanent does NOT mean that Sanctifying grace cannot be increased, decreased, or even lost through either our meritorious or despicable actions.
3. Sanctifying grace is communicated to man through the Sacraments of the Church, starting with Baptism. However, in every Sacrament, both Sanctifying and Actual graces are given.
, grace is the life of Christ.” Grace is “constantly and perennially” given to us through the communication of His Holy Spirit. One final point: Sanctifying grace and charity cannot be separated. They are either both present or both absent. St. John
When his words are taken in reference to those who are not ordained, I do not believe that Sanctifying / Sacramental / Habitual grace is the type of grace that he refers to when he tells St. Faustina that His grace will overflow from our souls and into other souls. Sanctifying grace is the result of direct communication between Jesus’ Holy Spirit and our spirit (the upper powers of the spiritual soul). It occurs via the instrumentality of the ordained priest who is in Persona Christi.
There are three exceptions. They are:
1). Jesus, whose humanity, both body and soul, is the instrument through which all of God’s grace enters into the world. His humanity does not cause grace, but because his human nature is hypostatically united with his Divine Nature, his humanity (body and soul) is the instrument by which we receive all grace, Sanctifying or otherwise;2). Bishops/priests who, through Holy Orders, receive an indelible mark on the soul, which enables them to confect the Sacraments in persona Christi. In other words, it is Jesus (the High Priest) who is confecting the Sacraments using the priest’s humanity as an instrument, and;3). Mary, whose union with her son is unique among all creation and doctrinally defined as the Mediatrix of all Grace.
Here’s something to ponder. If the soul is indelibly marked, wouldn’t the body also be so marked? Affect the dwelling place of the Holy Spirit (i.e., the spirit); then, it must also be true that the entire soul would be affected. Thus, the lower powers of the soul would cause change to the body. After all, the soul is the substantial form of the body. St. Catherine of Siena tells us, through the power of the purified soul on the day of our resurrection, our body will be imprinted with the fruits of the sufferings and labors endured by the body in partnership with the spiritual soul.
I believe the channeling of grace by ordinary man is this: a heart purified by Sanctifying grace and inhabited by the Holy Spirit (who always brings with him the infused virtue of charity) cannot help but overflow (express) in love, i.e., in charity. Were this not so, then both Hardon  and Aquinas [St. Thomas Aquinas, De Veritate, XXVII, 2 (corpus)] would be wrong to contend that both Sanctifying grace and infused charity are inseparable. According to Archbishop Luis Martinez, the virtue of infused charity is God's image and the perfect image of the Holy Spirit, who is uncreated Charity. Archbishop Martinez writes, “The Christian spirit is a spirit of charity, and charity requires communication [i.e., the expression of actual grace] — and not only charity, but justice and many other virtues as well.”
Before going on to a discussion about Actual Grace, I want to make one thing very clear about Sanctifying Grace. Indeed, the body does not radiate sacramental Sanctifying Grace. However, it is also true that, without a human body, it would be impossible for fallen man to receive Sanctifying Grace. Jesus tells us, “Truly, truly, I say to you, unless you eat the flesh of the Son of man and drink his blood, you have no life in you” (Jn. 6:53). Notice that Jesus didn’t say: unless you become one with my human soul, you have no life. Jesus also said, “He who eats my flesh and drinks my blood abides in me, and I in him” (Jn. 6:56). Notice also; he didn’t say, if you invite me into your heart, I will abide in you and you in me.
 Hardon, John (2013-06-25). “Sanctifying Grace,” Catholic Dictionary: An Abridged and Updated Edition of Modern Catholic Dictionary (p. 456). The Doubleday Religious Publishing Group. Kindle Edition.
 CCC, n. 460.
 Fr. John A. Hardon S.J., “History and Theology of Grace: Sanctifying Grace,” The Real Presence Association, http://www.therealpresence.org/archives/Grace/Grace_011.htm: Inter Mirifica, 1998 (accessed 06/23/2014). Used with permission from Inter Mirifica.
 Hardon, Catholic Dictionary: An Abridged and Updated Edition of Modern Catholic Dictionary, p. 456.
 Hardon, John (2013-06-25). “Sacramental Grace.” Catholic Dictionary: An Abridged and Updated Edition of Modern Catholic Dictionary (p. 442). The Doubleday Religious Publishing Group. Kindle Edition.
 Hardon. “Sanctifying Grace,” Catholic Dictionary: An Abridged and Updated Edition of Modern Catholic Dictionary, p. 456.
 Aquinas, Summa Theologiae, I-II, q. 112, a. 1.
 F.M. Jelly, O.P., “Mary, Mother Of The Church,” Our Sunday Visitor’s Encyclopedia of Catholic Doctrine, ed. Russell Shaw (Our Sunday Visitor Inc., Huntington, IN, 1997 ), pg. 423-427. For more information on this topic, some of F.M. Jelly O.P. recommends are the following sources: CCC 964-970; Lumen Gentium; Redemptoris Mater; Theotokos: A Theological Encyclopedia of the Blessed Virgin Mary by Michael O’Carroll. I would also add Tim Staples book, Behold Your Mother.
 Catherine of Siena, The Dialogue, 86.
 Hardon, “History and Theology of Grace: Sanctifying Grace,” http://www.therealpresence.org/archives/Grace/Grace_011.htm.
 John A. Hardon S.J., “History and Theology of Grace: Actual Graces,” The Real Presence Association, http://www.therealpresence.org/archives/Grace/Grace_013.htm: therealpresence.org, 1998 (accessed 05/08/2014).
 Ibid., 71.
 Ibid., 163.