A
A.D.
Aaron
Aaronites
Abba

Abel

Ablution

Abortion

Abraham

Abram

Absolution

Abstinence

Acts of the Apostles

Adam

Adoration

Adoration of the Eucharist
Adoration, Perpetual

Advent 

Advent Wreath

Agape

Alleluia

Amen

Amos, The Book of

Anathema

Andrew

Angel

Angelus
Ann

Annunciation
Anointing of the Sick

Anointing

Antichrist

Apocalyse

Apologetics

Apostles, Acts of the

Apostolic Succession

Archangels

Article of Faith
Ascension
Assumption
Authority

B

Baal

Bagoas

Baptism, Sacrament of

Barabbas

Barnabas

Bartholomew

Baruch, The Book of

Beatific Vision

Beatification

Beelzebub

Benediction of the Blessed Sacrament

Benediction, Apostolic

Benjamin

Bilocation

Bishop

Blessed

Blessed Sacrament

Blessed Virgin Mary

Bodily Immortality

Bodily Resurrection

Burial, Christian

C

Caesar

Caesar, Augustus

Caiaphas

Cain

Calumny

Calvary

Canon

Canon law

Canonization

Canticle of Canticles

Capital Punishment

Cardinal

Catacombs

Catechism

Catechumenate

Cathedral

Catholic

Chair of Peter

Charismatic Movement

Charity

Chastity

Childlikeness

Choir

Christ

Christian

Christmas

Chronicles, The First and Second Books of

Church Militant

Church Suffering

Church Triumphant

Church

Coliseum

Colossians, The Letter to the.

Communal Penance

Communion

Consecration to Mary

Contraception

Corinthians, Letters to the

Corporal Works of Mercy

Crucifixion

D

Daniel
Daniel, The book of.
David
Deacon
Dead Sea Scrolls
Deuteronomy, The book of.
Devil
Discernment of Spirits
Divine Mercy
Divine Office
Divorce
Doctrine
Dolors, Seven
Drunkenness

E

Easter Communion
Ecclesiastes, The book of
Ecumenism
Efficacious Grace
Emmanuel
Encyclical
Envy
Ephesians, The Letter to the.
Episcopacy
Eschatology
Esther, The Book of.
Eternal Law
Eternal Punishment
Eucharist
Eucharistic prayer
Evangelization
Eve
Evil
Ex Cathedra
Ex Opere Operantis
Ex Opere Operato
Excommunication
Exodus, The book of
Exorcism
Expiation
Exposition of the Blessed Sacrament
Extreme Unction 
Ezekiel
Ezra

F

Faith
Fall
Fasting
Father
Fathers of the Church
Fifteen Marks of the Church
Filioque
First Cause
First Communion
Flag, Papal
Font
Forgiveness
Fortitude
Free will

G

Gabriel, Angel
Galatians, The letter to the.
Gaudete Sunday
Genesis, The book of.
Gifts of the Holy Spirit
Glorified Body
Gluttony
God
God the Father
God the Holy Spirit
God the Son
Good Friday
Good Shepherd
Goodness of God
Gospel
Gospels, Apocryphal
Greed
Guadalupe
Guardian angel
Guilt

H

Habakkuk
Habit, Religious
Hagar
Haggai, The Book of
Hail Mary
Heart
Heaven
Hebrews, The letter to the
Hell
Heresy
Hermit
Heroic Virtue
Hierarchy
Holiness
Holy Communion
Holy Days of Obligation
Holy Saturday
Holy Spirit
Holy Thursday
Holy Water
Holy Week
Homily
Homosexuality
Hope
Hope, Act of
Hosea
Humility

I

Icon
Idolatry
Image of God
Immaculate Conception
Immaculate Heart
Immovable feasts
Incarnation
Indissoluble Marriage
Indwelling
Infallibility
Infants, Unbaptized
Infidelity
Inquisition
Intercession
Interior Struggle
Isaac
Isaiah, The book of
Israel

J

Jacob
James the Greater, Saint
James, The Letter of
Jeremiah
Jesus Christ
Jesus
Job
Joel, The book of
John the Baptist, Saint
John, Saint

John, The First, Second, Third Letter of

John, The Gospel of

Jonah, The book of

Jonathan
Joseph
Joseph, St.
Joshua, The book of

Joy
Judas Iscariot
Jude, Epistle of
Judges, The book of

Judgment, General
Judgment, Particular
Judgment
Judith, The book of
Jurisdiction
Just War Theory
Justice

K

Kings, The First and Second books of
Kissing the Altar

L

Laetare Sunday
Laity
Lamentations, The Book of
Last Sacraments
Last Supper
Latin
Latria
Lazarus
Lent
Leviticus, The book of.
Liberation Theology
Life Everlasting
Liturgy
Liturgy of the Eucharist
Liturgy of the Word
Lord
Lourdes
Love
Love of Enemies
Luke
Luke, The Gospel of
Lying

M

Maccabees, The First and Second Books of.
Magi
Magisterium of the Church
Malachi, The book of
Mandatum
Marian year
Mark
Mark, The Gospel of
Marks of the Church
Martyr
Mary Magdalene, Saint
Mary, Blessed Virgin
Mass
Mass Obligation
Matrimony
Matter of a Sacrament
Matthew, Saint
Matthew, The Gospel of
Medals
Melchizedek
Messiah
Micah, The book of
Miraculous Medal
Missal
Monstrance
Mortal sin
Moses
Mother of the Church
Mystical Body

N

Nahum, The book of
Natural Family Planning
Nature
Nehemiah, The book of
New Age
Nicene Creed
Numbers, The book of

O

Oath
Obadiah, The book of
Omission
Omniscience
Original Justice
Original Sin

P

Paraclete
Parousia
Particular Judgment
Patience
Patron Saint
Paul, saint
Pentecost
Perfect Happiness
Persecution
Peter, First Letter of
Peter, Saint
Peter, Second Letter of
Pharisees
Philemon
Philemon, Letter to
Philip
Philip, The Evangelist
Philippians, Letter to the
Pilate, Pontius
Pope
Prayer
Pride
Priest, Priesthood
Procreative Love
Prophet
Protestantism
Protoevangelium
Psalms, The book of
Purity

Q

R

Real Presence
Reconciliation
Redemption
Reformation
Relics
Religion
Religious State
Remission of Sin
Renewal
Renouncing Satan
Responsorial Psalm
Resurrection of Christ
Revelation, Private

Revelation, Public
Revelation, The Book of
Reverence
Rite of Christian Initiation of Adults (RCIA)
Romans, Letter to the
Rome
Rosary
Ruth, The book of

S

Sacrament
Sacrament of Penance
Sacrament of the Altar
Sacramental
Sacramental Character
Sacramental Matter and Form
Sacred Heart of Jesus
Sacrifice
Sadducees
Saints
Salvation
Samaritans
Samuel, The First and Second Books of
Satan
Savior
Scapular
Seal of confession
Seal of Confirmation
Second Adam
Second Coming of Christ
Second Vatican Council
Seminary
Separated Brethren
Septuagint
Service
Seven Sacraments
Seven Words of Christ
Shrine
Sign of the Cross
Sin
Sins against the Holy Spirit
Sirach, The book of
Sister, Religious
Slain in the Spirit
Solemnity
Solomon
Son of God
Son of Man
Song of Songs, The
Soul
Spiritual Life
Spiritual Works of Mercy
Sponsor
St. Joseph, Devotion to
State of grace
Stations of the Cross
Stephen
Sterilization
Stigmata
Suffering
Sunday
Synod
Synoptics

T

Tabernacle
Temperance
Temporary Vow
Temptation
Ten Commandments
Thaddeus
Theological virtue
Theology
Theophany
Theotokos
Thessalonians, First and Second Letters to the
Thomas, Saint
Thurible
Timothy
Timothy, First Letter to
Timothy, Second Letter to
Titus, Letter to
Tobit, The book of
Torah
Transfiguration
Transubstantiation
Tribunal
Tridentine Mass
Triduum
Trinity, Blessed
Trust
Truth

U

Unbaptized Infants
Unction
Unpardonable Sin

V

Vatican
Vatican City
Venerable
Veneration of Saints
Venial Sin
Vestments
Viaticum
Vicar Apostolic
Vicar General
Vicar of Christ
Vice
Vigil
Virgin Birth of Christ
Virgin Mary
Virginity
Virtue
Vocation
Vow
Vow of Chastity
Vow of Obedience
Vow of Poverty

W

Will of God
Will
Wisdom
Words of Absolution
Words of Institution

X

Xerxes I

Y

Yahweh
Year, Ecclesiastical
Yoga

Z

Zachary
Zeal
Zechariah, The book of
Zephaniah, The book of

Zucchetto