The following is an annotated glossary of terms related to Roman Catholic and Reformation studies.

ANATHEMA – A thing devoted or given over to evil, so that “anathema sit” means, “let him be accursed.” St. Paul at the end of 1 Corinthians pronounces this anathema on all who do not love our blessed Saviour. The Church has used the phrase “anathema sit” from the earliest times with reference to those whom she excludes from her communion either because of moral offences or because they persist in heresy. … In pronouncing anathema against wilful heretics, the Church does but declare that they are excluded from her communion, and that they must, if they continue obstinate, perish eternally.
A Catholic Dictionary, 24.

FAITH – Faith in God Involves Right Belief about God. The word faith in ordinary speech covers both credence of propositions (“beliefs”) and confidence in persons or things. … Faith Rests on Divine Testimony. Beliefs, as such, are convictions held on grounds, not of self-evidence, but of testimony. … Faith Is a Supernatural Divine Gift.
Evangelical Dictionary of Theology: Second Edition, 432.

GRACE – In Christian doctrine, this term refers to unmerited divine favor. In summary form, the Christian message is “the gospel of God’s grace” (Acts 20:24). The Greek term, charis was common in secular usage, but when taken up into the message of Christ it was to become filled out with a new and enriched content. Its usual meaning in classical Greek is “attractiveness” or “charm” (cf. the cognate verb chairō, “to rejoice, be glad”), though it can also be translated “favor, kindness, gratitude.” The word appears about 170 times in the Greek OT, where it commonly renders a Hebrew word of similar meaning, ḥēn (Gen. 6:8; 19:19). While the Septuagint has many expressions to convey the reality of God’s saving acts on behalf of men (e.g., eleos, “mercy, compassion,” rendering ḥesed), charis is not used in this connection.
The Zondervan Encyclopedia of the Bible, 840.

IMPUTATION – A broad concept finding its theological center in the atonement. The Latin imputare literally means “to reckon,” “to charge to one’s account,” and is an adequate rendering of the Greek term logizomai. This forensic notion of imputation has its partial roots in the commercial and legal language of the Greco-Roman world; those who have something imputed to them are accountable under the law. It is in this sense that Paul asks Philemon to have Onesimus’s debts transferred to Paul (Philem. 18: “If he has done you any wrong … charge it to me”). Imputation also has its distinctively Hebraic roots (cf. ḥāšab, “to count for, to reckon”), being used, for example, in reference to the sacrificial system (cf. Lev. 7:18: “neither shall it be credited to him”; Lev. 17:4). It is also important to note that the OT uses the term to include even those judgments that have no direct, objective basis (e.g., Gen. 31:15: “Does he not regard us as foreigners?”; 2 Chron. 9:20).

In the NT, Christians are said to receive the “alien righteousness” of God as a “gift that came by the grace of the one man, Jesus Christ” (Rom. 5:15). Just as God reckoned Abraham as righteous on the basis of Abraham’s belief alone (Gen. 15:6; Rom. 4:3), so others are similarly blessed as the Lord does not impute their iniquity to them (Ps. 32:1–2; Rom. 4:7–8). This divine judicial act is based, not on human merit, but on God’s love (Rom. 5:6–8).
EDT2, 600.

INDULGENCE – Indulgentia is a technical term in the Roman law, meaning amnesty or pardon; and in much the same sense it occurs in the Latin of the Vulgate, where it is synonymous with remissio as may be seen by comparing Isai. 61:1, with Luc. 4:18. In the language of the Church it has acquired a much more definite and restricted meaning, and an indulgence in the theological sense of the word is defined by Amort in his classical work on the subject, as “a remission of the punishment which is still due to sin after sacramental absolution, this remission being valid in the court of conscience and before God, and being made by an application of the treasure of the Church on the part of a lawful superior.”
A Catholic Dictionary, 440.

JUSTIFICATION – The basic fact of biblical religion is that God pardons and accepts believing sinners (see Pss. 32:1–5; 130; Luke 7:47–50; 18:9–14; Acts 10:43; 1 John 1:7–2:2). … The biblical meaning of “justify” (Hebrew, ṣādēq; Greek, LXX and NT, dikaioō) is to pronounce, accept, and treat as just, i.e., as, on the one hand, not penally liable, and, on the other, entitled to all the privileges due to those who have kept the law. It is thus a forensic term, denoting a judicial act of administering the law—in this case, by declaring a verdict of acquittal and so excluding all possibility of condemnation. Justification thus settles the legal status of the person justified (Deut. 25:1; Prov. 17:15; Rom. 8:33–34). The justifying action of the Creator, who is the royal Judge of this world, has both a sentential and an executive, or declarative, aspect: God justifies, first, by reaching his verdict and then by sovereign action makes his verdict known and secures to the person justified the rights that are now his due. What is envisaged in Isaiah 45:25 and 50:8, for instance, is specifically a series of events that will publicly vindicate those whom God holds to be in the right. … There is no lexical ground for the view of Chrysostom, Augustine, and the medieval and Roman theologians that “justify” means, or connotes as part of its meaning, “make righteous” (by subjective spiritual renewal). The Tridentine definition of justification as “not only the remission of sins, but also the sanctification and renewal of the inward man” (Sess. VI, ch. vii) is by biblical standards erroneous.
EDT2, 643-644.

MERIT – Generally (according to the Roman Catholic Church): The reward which God promises and gives to those who love him and by his grace perform good works. [§888]

The term “merit” refers in general to the recompense owed by a community or a society for the action of one of its members, experienced either as beneficial or harmful, deserving reward or punishment. Merit is relative to the virtue of justice, in conformity with the principle of equality which governs it. (§1723; 1807). [§486]
Catechism of the Catholic Church

Condign: Merit in the strict sense of the term, as in a moral act performed in a state of grace, and worthy of divine acceptation on that account. 
Congruous: Merit in a weak sense of the term, as in a moral act performed outside of a state of grace which, although not meritorious in the strict sense of the term, is considered an appropriate ground for the infusion of justifying grace.
McGrath, Iustitia Dei, 397.

PENANCE – The liturgical celebration of God’s forgiveness of the sins of the penitent, who is thus reconciled with God and with the Church. The acts of the penitent—contrition, the confession of sins, and satisfaction or reparation—together with the prayer of absolution by the priest, constitute the essential elements of the Sacrament of Penance (§980, 1422, 1440, 1448).
CCC, §892.

PURGATORY – A place in which souls who depart this life in the grace of God suffer for a time because they still need to be cleansed from venial, or have still to pay the temporal punishment due to mortal sins, the guilt and the eternal punishment of which have been remitted.
A Catholic Dictionary, 702.

Council of Trent on Purgatory

Whereas the Catholic Church, instructed by the Holy Ghost, has, from the sacred writings and the ancient tradition of the fathers, taught, in sacred councils, and very recently in this œcumenical synod, that there is a Purgatory, and that the souls there detained are relieved by the suffrages of the faithful, but chiefly by the acceptable sacrifice of the altar; the holy synod enjoins on bishops that they diligently strive that the sound doctrine touching Purgatory, delivered by the holy fathers and sacred councils, be believed, held, taught, and everywhere proclaimed by the faithful of Christ. But let the more difficult and subtle questions, and those which tend not to edification, and from which for the most part there is no increase of piety, be excluded from popular discourses before the uneducated multitude. In like manner, such things as are uncertain, or which labour under an appearance of error, let them not allow to be made public and treated of. But those things which tend to a certain kind of curiosity or superstition, or which savour of filthy lucre, let them prohibit as scandals and stumbling-blocks of the faithful. And let the bishops take care, that the suffrages of the faithful who are living, to wit, the sacrifices of masses, prayers, almsgivings, and other works of piety, which have been wont to be performed by the faithful for the other faithful departed, be piously and devoutly performed, according to the institutes of the Church; and that what things soever are due on their behalf from the endowments of testators, or in other way, be discharged, not in a negligent manner, but diligently and accurately, by the priests and ministers of the church, and others who are bound to render this service.
The Canons and Decrees of the Council of Trent, 212–213.

RELIC – The word includes the bodies of departed saints, fragments of their bodies, articles or portions of articles which they have used, such as clothes, vestments, rosaries, and the like. The Church also venerates relics of Christ and his Blessed Mother. Such are the holy nails, lance, spear, or fragments of the True Cross, the girdle, veil, &c., of the Blessed Virgin. The devotion to relics, solemnly approved by the Council of Trent (sess. xxv. De Invoc. Sanct.) rests on two great principles of Catholic belief.

First, the Church honours the bodies of the dead who sleep in Christ. … Next, Catholics believe that God is sometimes pleased to honour the relics of the saints by making them instruments of healing and other miracles, and also by bestowing spiritual graces on those who with pure hearts keep and honour them.
A Catholic Dictionary, 714.

REPENTANCE – Signifies a change of the mind from a rebellious and disaffected state to that submission and thorough separation from iniquity by which converted sinners are distinguished (Matt. 3:2–8).CBTEL

Generally, however, metanoia can be said to denote that inward change of mind, affections, convictions, and commitment rooted in the fear of God and sorrow for offenses committed against him, which, when accompanied by faith in Jesus Christ, results in an outward turning from sin to God and his service in all of life. It is never regretted (ametamelēton, 2 Cor. 7:10), and it is given by God (Acts 11:18). … Calvin taught that repentance stemmed from serious fear of God and consisted in the mortification of the old man and the quickening of the Spirit. Mortification and renovation are obtained by union with Christ in his death and resurrection (Institutes of the Christian Religion 3.3.5, 9). Beza (after Lactantius and Erasmus) objected to the translation metanoeō by “poenitentiam agite,” but the attempt to replace this with resipiscentia (“a coming to one’s self”) was infelicitous. Luther occasionally used “Thut Busse!” but his thesis was that Jesus, in giving this command, meant that all of life was to be penance before God. Roman Catholicism teaches that the sacrament of penance consists materially of contrition, confession, and satisfaction. But the judicial pronouncement of absolution by the church is needed to give these elements real validity.
Cyclopædia of Biblical, Theological, and Ecclesiastical Literature, 1042.
EDT2, 1012.

RIGHTEOUSNESS – The Hebrew word regularly translated “righteous” or “just” is ṣāddîq and originally meant “straight” or “right.” The corresponding Greek term is dikaios, and in Greek society referred to that which is in accordance with law or social norm. The noun forms are ṣedeq (or sĕdāqâ) and dikaiosynē. The verbs ṣādak and dikaioō mean “to do justice,” “to be just,” “to vindicate,” or “to justify” in the forensic sense of “declare righteous” or “treat as just.”
EDT2, 1033.

SACRAMENT – An efficacious sign of grace, instituted by Christ and entrusted to the Church, by which divine life is dispensed to us through the work of the Holy Spirit (§774, 1131). The sacraments (called “mysteries” in the Eastern Churches) are seven in number: Baptism, Confirmation, Eucharist, Penance or Reconciliation, Anointing of the Sick, Holy Orders, and Matrimony (§1210).
CCC, §898