Sola fide (Latin: by faith alone), also known as the doctrine of justification by faith alone, is a Christian theological doctrine that distinguishes most Protestant denominations from the Catholic Church, the Eastern Orthodox Church, and some parts of the Restoration Movement.
The doctrine of sola fide asserts God’s pardon for guilty sinners is granted to and received through faith alone, excluding all “works”. All mankind, it is asserted, is fallen and sinful, under the curse of God, and incapable of saving itself from God’s wrath and curse. But God, on the basis of the life, death, and resurrection of his Son, Jesus Christ alone (solus Christus), grants sinners judicial pardon, or justification, which is received solely through faith. Faith is seen as passive, merely receiving Christ and all his benefits, among which benefits are the active and passive righteousness of Jesus Christ. Christ’s righteousness, according to the followers of “sola fide,” is imputed (or attributed) by God to the believing sinner (as opposed to infused or imparted), so that the divine verdict and pardon of the believing sinner is based not upon anything in the sinner, nor even faith itself, but upon Jesus Christ and his righteousness alone, which are received through faith alone. Justification is by faith alone and is distinguished from the other graces of salvation. See the Protestant ordo salutis for more detail on the doctrine of salvation considered more broadly than justification by faith alone.
Historic Protestantism (both Lutheran and Reformed) has held to sola-fide justification in opposition to Roman Catholicism especially, but also in opposition to significant aspects of Eastern Orthodoxy. Protestants exclude all human works (except the works of Jesus Christ, which form the basis of justification) from the legal verdict (or pardon) of justification. In the General Council of Trent the Catholic Church stated in canon XIV on justification that “If any one saith, that man is truly absolved from his sins and justified, because that he assuredly believed himself absolved and justified; or, that no one is truly justified but he who believes himself justified; and that, by this faith alone, absolution and justification are effected; let him be anathema (excommunicated).” Thus, “faith alone” is foundational to Protestantism, and distinguishes it from other Christian denominations. According to Martin Luther, justification by faith alone is the article on which the church stands or falls.