Anything that falls short of or rebels against God and his will, whether in action, word, thought, or what is left undone.

One common Greek word for it means "to miss the mark". The Bible treats sin not only as individual wrong acts but as a power and a condition that affects every person and the whole world, which is why forgiveness alone is not the whole answer. It damages a person's relationship with God first, and every other relationship follows.

Romans 3:23

God's undeserved kindness and favour, given freely rather than earned.

The idea runs from the Old Testament, where God describes himself as "merciful and gracious", to Paul's letters, where it is at the centre of salvation. Grace is often paired with mercy: mercy is not getting the punishment you deserve, and grace is getting the good you do not deserve.

Exodus 34:6

The way the broken relationship between God and people is repaired and sin is dealt with. The English word was coined from "at-one-ment".

In the Old Testament, atonement came through sacrifices, especially on the yearly Day of Atonement, when the high priest entered the Most Holy Place. The New Testament presents Jesus's death as the final sacrifice that those foreshadowed. Christians have described how it works in several ways — as a sacrifice, a ransom, a victory over evil, and bearing the penalty in our place — and the traditions weigh these differently.

Leviticus 16:30

"Anointed one". Kings and priests in Israel were anointed with oil, and the Messiah was the promised king from David's line who would set everything right.

The Greek translation of the word is Christos, which gives us "Christ". By Jesus's time many Jews expected a Messiah who would drive out Rome and restore Israel's kingdom. Part of the tension in the Gospels is that Jesus accepts the title but redefines it around suffering and death.

Mark 8:29-31

Good news, specifically the announcement that God's kingdom has come in Jesus, who died for sins and rose from the dead.

The Greek word, euangelion, was used in the Roman world for announcements like a military victory or the birth of an heir to the emperor. The early Christians borrowed it deliberately. "Evangelism" and "evangelical" come from the same word. The four books called Gospels are named for their message.

1 Corinthians 15:3-4

God's rule, breaking into the world through Jesus, and the renewed world where that rule will be complete.

It was the main subject of Jesus's preaching and of most of his parables. It is not a place on a map or simply heaven after death; it is God's reign becoming real, which is why Jesus taught people to pray "your kingdom come, your will be done, on earth as it is in heaven". Matthew usually says "kingdom of heaven", a reverent Jewish way of avoiding the word God, but it means the same thing.

Mark 1:15

Being declared right with God, acquitted and accepted, as a gift received through faith in Christ rather than earned.

It is a courtroom word: the judge declares the defendant in the right. For Paul it is the answer to how guilty people can stand before a just God. The meaning of justification was the central dispute of the Protestant Reformation, and Christian traditions still describe it in different ways.

Romans 5:1

Turning around: a change of mind and direction, away from sin and toward God.

The Hebrew idea is literally turning back, and the Greek word, metanoia, means a change of mind. It is more than feeling sorry; it is a change in where a person is heading. Both John the Baptist and Jesus began their preaching with the call to repent.

Matthew 4:17

Set apart: belonging to God and therefore different from the ordinary. God himself is holy, meaning utterly distinct in purity and majesty.

Places, days, objects, and people can all be holy because they are set apart for God. Isaiah's vision has angels calling "holy, holy, holy", repeated three times for emphasis, the only attribute of God raised to that degree. God's repeated command to his people is "be holy, for I am holy".

Isaiah 6:3

The Christian belief that there is one God who exists eternally as three persons: the Father, the Son, and the Holy Spirit.

The word "Trinity" is not in the Bible; it was coined to summarise what the church saw in it. The Old Testament insists there is only one God, yet the New Testament speaks of Jesus and the Spirit as God while distinguishing them from the Father. The doctrine was formally defined at the councils of Nicaea (AD 325) and Constantinople (381), and it is shared by Catholic, Orthodox, and Protestant churches.

Matthew 28:19

That humans, male and female, are made to reflect God and represent his rule in the world, which gives every person dignity.

In the ancient world, kings set up images of themselves to mark their authority in a territory. Genesis says every human being, not just the king, is God's image in the world. The New Testament calls Christ the true image of God, and describes salvation as being renewed into that image.

Genesis 1:27

Being raised bodily from death to a new, imperishable life — first Jesus, and at the end, all who belong to him.

It is not the same as the soul going to heaven after death, and it is not a corpse being revived only to die again, as Lazarus did. Paul calls Jesus's resurrection the "firstfruits", the first part of a harvest that guarantees the rest. He says that if Christ has not been raised, Christian faith is worthless.

1 Corinthians 15:20

It is his favourite title for himself, drawn from Daniel's vision of "one like a son of man" who receives an everlasting kingdom from God.

In ordinary Hebrew and Aramaic it could simply mean "a human being", which let Jesus use it without making an obvious public claim. But in Daniel it is a heavenly figure who rules forever. At his trial Jesus quoted Daniel's vision directly, and the high priest tore his clothes and called it blasphemy.

Mark 14:61-64