Sanctification in Christianity

In Christianity, sanctification literally means "to set apart for special use or purpose", that is, to make holy or sacred. Therefore, sanctification refers to the state or process of being set apart, i.e. "made holy", as a vessel, full of the Holy Spirit. The term can be used to refer to objects which are set apart for special purposes, but the most common use within Christian theology is in reference to the change brought about by God in a believer, begun at the point of salvation and continuing throughout the life of the believer. When used in this sense, sanctification is known as growth in grace. Many forms of Christianity believe that this process will only be completed in Heaven, but some believe that entire sanctification is possible in this life.

Teaching by Christian denomination

Roman Catholicism

The Catholic Church upholds the doctrine of sanctification, teaching that:
Saint Paul of the Cross stated that "Prayer, good reading, the frequent reception of the sacraments, with the proper dispositions, and particularly the flight of idleness—these are, believe me, the means of sanctifying yourself."
According to the Catholic Encyclopedia "sanctity" differs for God, individual, and corporate body. For God, it is God's unique absolute moral perfection. For the individual, it is a close union with God and the resulting moral perfection. It is essentially of God, by a divine gift. For a society, it is the ability to produce and secure holiness in its members, who display a real, not merely nominal, holiness. The Church's holiness is beyond human power, beyond natural power.

Eastern Orthodoxy

teaches the doctrine of theosis, whereby humans take on divine properties, and in a particular sense, participate in the being of God. A key scripture supporting this is 2 Peter 1:4. In the 4th century, Athanasius of Alexandria taught that God became Man that man might become God. Essentially, man does not become divine, but in Christ can partake of divine nature. This Church's version of salvation restores the likeness of God in man. One such theme is release from mortality caused by desires of the world.

Lutheranism

At the time of the justification of an individual, the Lutheran Churches teach that the process of sanctification commences, which is defined as "the Holy Spirit’s work which follows justification through faith and consists of renewing the believer and bringing forth in him works of renewal." In Lutheranism, sanctification has two components, including: "1.) The inner renewal of the Holy Spirit in the Christian, and 2.) the living out of that inner renewal in the Christian’s new life of good works." The Lutheran Confessions hold that it is "necessary to exhort people to Christian discipline and good works, and to remind them how necessary it is that they exercise themselves in good words as an evidence of their faith and their gratitude toward God". For Christians, "good works are necessary fruits of faith in the life of a Christian and that they proceed from a renewed heart that is thankful to God for His mercy and love". These good works done by Christians are rewarded by God. Those individuals who commit mortal sin "render themselves subject to divine wrath and eternal death unless, turned again, they are reconciled to God through faith." The Formula of Concord summarizes salvation in Lutheran Christianity:
The Lutheran Confessions state:
Martin Luther taught in his Large Catechism that Sanctification is only caused by the Holy Spirit through the powerful Word of God. The Holy Spirit uses churches to gather believers together for the teaching and preaching of the Word of God.
In the process of sanctification, humans cooperate with God, enabled by prevenient grace "for the Holy Spirit is given credit for our faith and for the surrender of the will to God." The Formula of Concord teaches: "But the intellect and will of the unregenerate man are nothing else than subiectum convertendum, that is, that which is to be converted, it being the intellect and will of a spiritually dead man, in whom the Holy Ghost works conversion and renewal, towards which work man’s will that is to be converted does nothing, but suffers God alone to work in him, until he is regenerate; and then he works also with the Holy Ghost that which is pleasing to God in other good works that follow, in the way and to the extent fully set forth above". The Lutheran Churches teach that God rewards good works done by Christians; the Apology of the Augsburg Confession teaches: "We also affirm what we have often said, that although justification and eternal life go along with faith, nevertheless, good works merit other bodily and spiritual rewards and degrees of reward. According to 1 Corinthians 3:8, ‘Each will receive his wages according to his labor.’"
Luther viewed the Ten Commandments as a means by which the Holy Spirit sanctifies:

"Thus we have the Ten Commandments, a commend of divine doctrine, as to what we are to do in order that our whole life may be pleasing to God, and the true fountain and channel from and in which everything must arise and flow that is to be a good work, so that outside of the Ten Commandments no work or thing can be good or pleasing to God, however great or precious it be in the eyes of the world...whoever does attain to them is a heavenly, angelic man, far above all holiness of the world. Only occupy yourself with them, and try your best, apply all power and ability, and you will find so much to do that you will neither seek nor esteem any other work or holiness."

Pietistic Lutheranism heavily emphasizes the "biblical divine commands of believers to live a holy life and to strive for holy living, or sanctification."

Anabaptism

belief emphasizes that sanctification is initiated by being born again by the Spirit of God and then practiced by following or being a disciple of Christ. The role of the Spirit, Word of God, suffering, self-denial as well as the community of believers in sanctification is also considered essential. Sanctification is believed to be a process that begins with conversion and continues throughout the Christian life. Perfectionism or eradication of the flesh is rejected and it is considered necessary to take up the cross and deny yourself daily to truly be a disciple of Christ. When a believer steps out of the sanctification process, his salvation is seen as jeopardized. Sanctification is seen as mortifying the deeds of the flesh, cleansing impure motives and thoughts of the mind and heart as well as glorifying the Father through worship, obedience and faith working in love.

Anglicanism

A 2002 Anglican publishing house book states that “there is no explicit teaching on sanctification in the Anglican formularies”. A glossary of the Episcopal Church gives some teaching: “Anglican formularies have tended to speak of sanctification as the process of God's work within us by means of which we grow into the fullness of the redeemed life.” Outside official formularies sanctification has been an issue in the Anglican Communion since its inception.
The 16th century Anglican theologian Richard Hooker distinguished between the “righteousness of justification” that is imputed by God and the “righteousness of sanctification” that comprises the works one does as an “inevitable” result of being justified.
Jeremy Taylor argued that justification and sanctification cannot be separated; they are “two steps in a long process”.
A 19th century Church of England work agreed with Jeremy Taylor that justification and sanctification are “inseparable”. However, they are not the same thing. Justification is “found in Christ's work alone”. “Sanctification is the work of the Holy Spirit in us, and is a progressive work.”

Baptist

believe in progressive sanctification, the work of sanctification of the believer through grace and the decisions of the believer after the new birth.

Reformed

It is not clear that John Calvin, in his Institutes of the Christian Religion, conceives of sanctification as a doctrine separate from justification. There is no separate treatment there of a doctrine of sanctification. Instead, the clearest references he makes to the process of the Christian's growth in holiness appear in Book III of the Institutes, which concerns the work of the Holy Spirit. There he intermixes the grace by which justification is accomplished and the grace that empowers the Christian toward moral reform. Following Augustine, Calvin embraces a non-perfectionist account of sanctification as progressive but incomplete until eschatological consummation:

"I insist not that the life of the Christian shall breathe nothing but the perfect Gospel, though this is to be desired, and ought to be attempted. I insist not so strictly on evangelical perfection, as to refuse to acknowledge as a Christian any man who has not attained it. In this way all would be excluded from the church, since there is no man who is not far removed from this perfection, while many, who have made but little progress, would be undeservedly rejected."

Against those who "maintain the perfection of holiness in the present life," Calvin replies:

"...we deem it sufficient briefly to reply with Augustine, that the goal to which all the pious ought to aspire is, to appear in the presence of God without spot or blemish; but as the course of the present life is at best nothing more than progress, we shall never reach the goal until we have laid aside the body of sin, and been completely united to the Lord."

But the imperfection of sanctification in this life is not, for Calvin, an excuse for slackness in the search thereof. The grace of justification is not separable from the grace that makes one perform good works and the grace that perfects what is deficient in the works of the regenerate:

“Justification, moreover, we thus define: the sinner being admitted into communion with Christ is, for his sake, reconciled to God; when purged by his blood he obtains the remission of sins, and clothed with righteousness, just as if it were his own, stands secure before the judgment seat of heaven. Forgiveness of sins being previously given, the good works which follow have a value different from their merit, because whatever is imperfect in them is covered by the perfection of Christ, and all their blemishes and pollutions are wiped away by his purity, so as never to come under the cognizance of the divine tribunal. The guilt of all transgressions, by which men are prevented from offering God an acceptable service, being thus effaced, and the imperfection which is wont to sully even good works being buried, the good works which are done by believers are deemed righteous, or, which is the same thing, are imputed for righteousness.”