The heavenly Father has a grand plan for the life of every person, and it can be summed up in the word sanctification. If you have never been certain of the term's meaning, you are not alone--many people are unclear about its definition. However, believers should understand it because the word defines them.
In its verb form--sanctify--the term means "to make holy" or "to separate." So when something is sanctified, it is separated from its former common usage and is dedicated for sacred purposes. The Old Testament mentions a number of things that the Lord sanctified: He made the seventh day holy, set aside the Levite tribe as priests, and even consecrated places like the Holy of Holies inside the tabernacle (Gen. 2:3; Num. 3).
The heavenly Father still sanctifies people today. Before a person places his faith in the Savior, he is spiritually dead and, in fact, an enemy of God (Eph. 2:1-3; Rom. 5:10). But the moment someone chooses to trust in Jesus Christ, his sins are wiped away, and he is adopted into God's family. That individual is set apart as a child of God, with a sacred purpose. This means believers are not here to chase after personal gain but to serve the Lord and bring Him honor and glory.
As members of God's family who are called upon to reflect His glory, believers are referred to as "saints." We are given this moniker--which shares its root with sanctification--not because we live sinless lives, but because we live a life consistent with the One we represent.