Key Terms and Concepts in Catholic Theology

A collection of vocabulary terms and definitions relevant to Catholic theology, focusing on sacraments, sin, and moral guidance.

Absolution

The forgiveness we receive from God through the priest.

Soul

The soul is a mortal created immediately by God and is responsible for our consciousness.

Repentance

Our turning away from sin with the desire to change our lives to live as God wants us to.

Calis

The sacred vessel in which the wine is transformed into the blood of Christ during Mass.

Conscience

The inner voice that helps us judge the morality of our actions, guiding us to do good and avoid evil.

Confess

To admit having done something that has hurt our relationship with God and others.

Consecration

The words spoken by the priest that transform the bread and wine into the body and blood of Christ.

Contrition

The sorrow we feel when we know we have sinned, followed by the decision to not sin again.

Mortal choice

The decision to do what is right or to not do what is wrong.

Holy Spirit

The third person of the Trinity, sent to be our helper and fill us with God's life.

Eucharist

The sacrament through which we give thanks to God for giving us the body and blood of Christ.

Gospel

The good news of God's mercy and love, revealed through Jesus' life, death, and resurrection.

Examination of conscience

The prayerful reflection on our actions and how they may have impacted our relationship with God or others.

Grace

The gift of God given without our deserving it, filling us with God's life.

Host

The unleavened bread at Mass that is transformed into the body of Christ.

Free will

The ability to choose to do good as we are made in God's image.

Mass

The most important sacrament of the church, established by Jesus at the Last Supper.

Our Father

The prayer that Jesus taught his disciples and the church.

Sin of omission

The failure to act according to our firm judgment of conscience.

Mortal sin

A decision to turn away from God by committing something we know is seriously wrong.

Original sin

The consequence of the disobedience of Adam and Eve.

Venial sin

A choice we make that weakens our relationship with God or others.

Real presence

The way in which Jesus is present in the Eucharist under the appearance of bread and wine.

Seven sacraments

The means through which God's life enters our life through the Holy Spirit.

Sacrifice

The offering of Jesus of himself when he died on the cross for our forgiveness.

Temptation

An attraction, either external or internal, that can lead us to disobey God's commands.

Transubstantiation

The process by which the bread and wine become the body and blood of Christ.

Tabernacle

The container in which the Eucharist is kept.