Who were considered "Saints"?
Background
The word often translated as "saints" literally means "holy ones" or further yet "set apart ones". There were different types of holy ones. Israel was set apart from the world as God's nation and so they were all considered "holy ones". Those who were set apart for ministering to God were called "holy ones" and so angels were referred to as "holy ones" as well as priests (Ezekiel 44:11, Psalm 16:3, Maccabees 7:17).
The False Teaching
Those who followed the
Way of the Spirit would stay in the good part of
Hades and not be resurrected. Those who followed the
Way of the Flesh would ascend into heaven, be resurrected and inherit the kingdom except for women, children and slaves.
New Testament Response
Paul responds by saying that they were all holy ones:
1 Corinthians 1:2
to the assembly of God which is at Corinth; those who are made holy in Christ Jesus, called to be holy ones, with all who call on the name of our Lord Jesus Christ in every place, both theirs and ours:
Romans 1:7
to all who are in Rome, beloved of God, called to be holy ones: Grace to you and peace from God our Father and the Lord Jesus Christ.
Related Verses in Ephesians:
Eph. 1:1,
Eph. 1:15,
Eph. 1:18
Service
The False Teaching
Those who were not holy ones would serve the ones who were.
New Testament Response
New Testament writers respond by saying that they are all saints and that they should all serve each other:
Hebrews 6:10
For God is not unrighteous, so as to forget your work and the labor of love which you showed toward his name, in that you served the holy ones, and still do serve them.
(See also 1 Cor. 16:15, 2 Cor. 8:4, 2 Cor 9:1, 1 Tim. 3:13)