The word saint can mean different things to different people—a good person, a religious person, a person of great stature in a church or denomination, even a neighborly person can acquire the title of “Saint”—but the only thing that really matters is what it means to God.
The Greek word in Colossians 1:2 for saints is hagio and means holy or sacred. “Set apart” or “called out” are terms we might use to describe a saint. It has to do with religious dedication or consecration. Saints, in New Testament times were simply those persons who were dedicated to their own god.
Paul (the author of Colossians) coined a new meaning of the word when he addressed the “saints” in Colossae. Why? Because Colossae was a hideously heathen town! Temples were on every corner with tons of saints dedicated to their own gods. Paul was not writing to the town of Colossae at large, nor was he writing to just any ol’ saint in the town of Colossae.
By adding the requirement of being a faithful brother he clearly defined his audience. Paul was only writing to those whose dedication belonged to the One and Only True God—the God of the Jews! He was addressing only those who were true believers and faithful brethren in Christ Jesus…
That was Paul’s definition of a true saint because that is God’s criteria!
To be a neighborly person, a good person, a religious person, or even a person of great stature in a church or denomination is of no value, now or ever, if you are not set apart to the One and Only True God. Only when you are in Christ will you be consecrated to Him, holy to Him, and dedicated to following Him and His ways. Only then will you be a saint of the Most High God and bring Him the Glory He demands.