In the Old Testament, the word translated "saint" is the Hebrew qadowsh. It means sacred, Holy One, set apart. It does not only refer to people (Psalm 16:3) but, as the adjective "holy," also describes a place (Leviticus 6:16), food (Leviticus 7:6), and God (Leviticus 20:26). The Aramaic qaddiysh is related (Daniel 7:22). The word "saint" in the New Testament is the Greek agioss. It can also be translated holy and refers to people (Matthew 27:52), the Holy Spirit (Matthew 1:18), Jerusalem (Matthew 4:5), the Holy of Holies in the Temple (Matthew 24:15), prophets (Acts 3:21), and general believers (2 Corinthians 1:1). Nowhere is the term restricted to a particular class of individual that is granted the title by the organizational authorities of a religion.
What does it mean to be a Christian saint?
The concept of a Catholic saint is a little different. Catholicism takes the cloud of witnesses surrounding us from Hebrews 12:1 and combines them with the prayers of the righteous in James 5:16 to derive the belief that people who were especially pious on earth can pray for others from heaven. Identifying these deceased prayer-warriors was difficult until the Catholic Church enacted a policy that gives the exact qualifications.
Other religions have different definitions of saints. Eastern Orthodox says that any believer who is in Heaven is a saint, whether those on earth know it or not; the title has little to do with behavior or piety. In Buddhism, an Arhat is a person who has found release from the cares of this world and has achieved nirvana. The Bhagat of the Sikh religion are also a type of saint. In modern vernacular, a "saint" is anyone who is kind, generous, or follows the rules.
The Bible defines the Christian saint as anyone who follows Jesus. Every Christian is set apart from the world, to do good works through Jesus. The term "saint" is a reflection of the changes God makes in us, not our success in embodying those changes.
A Christian saint can be:
Dead (Matthew 27:52): "The tombs also were opened. And many bodies of the saints who had fallen asleep were raised…"
Alive (Acts 9:32): "Now as Peter went here and there among them all, he came down also to the saints who lived at Lydda."
Inclusive (Romans 16:15): "Greet Philologus, Julia, Nereus and his sister, and Olympas, and all the saints who are with them."
Anointed by God (1 Corinthians 1:2): "To the church of God which is at Corinth, to those who have been sanctified in Christ Jesus, saints by calling, with all who in every place call on the name of our Lord Jesus Christ, their Lord and ours…"
Non-exclusive (Philippians 1:1 NASB): "Paul and Timothy, bond-servants of Christ Jesus, to all the saints in Christ Jesus who are in Philippi, including the overseers and deacons…"
Non-influential (Revelation 11:18): "The nations raged, but your wrath came, and the time for the dead to be judged, and for rewarding your servants, the prophets and saints, and those who fear your name, both small and great, and for destroying the destroyers of the earth."
A saint is not someone who is particularly pious, whose prayers cause miracles, or who sacrifices a great deal for their faith. According to the Bible, a saint is just someone who has accepted Christ as their savior.
Is entire sanctification possible? Can Christians achieve sinless perfection in this life?
What does it mean for Christians to be in the world but not of the world?
Religiosity - What is it?
Freedom in Christ - What is it? How can I experience true freedom in Christ?
How important is spiritual growth in Christian life?
Truth about the Christian Life