Saint.
Two words are employed in the Hebrew.
1. chasid, 'pious toward God,' also translated 'holy' and 'godly.' The word occurs frequently in the Psalms, where God speaks of His saints. Psalms 31:23; Psalms 50:5; Psalms 116:15; Psalms 149:1, Psalms 1:149, Psalms 1:149; etc.
2. qadosh, 'consecrated, set apart, holy.' Deuteronomy 33:3; Job 15:15; Psalms 16:3; Psalms 34:9; Psalms 89:5, Psalms 1:89; Daniel 7:18-27; Daniel 8:13; Hosea 11:12; Zechariah 14:5. Aaron is called 'the saint of Jehovah.' Psalms 106:16.
In the N.T. the word used is agios, which means 'holy one.' A saint is one set apart for God; he is such by calling (not 'called to be a saint'). Romans 1:7; 1 Corinthians 1:1; cf. Hebrews 3:1. Saints are thus a distinct, recognised class of persons belonging to God — His saints. Acts 9:13; Colossians 1:26; 1 Thessalonians 1:3; Jude 1. All Christians are embraced in this class, so that the apostle could speak of 'all saints.' Ephesians 1:15; Ephesians 3:18; Colossians 1:4; Philemon 1. Christians therefore need not shrink from acknowledging the designation by which God has been pleased to distinguish them, and should ever remember that there is a line of conduct that 'becometh saints.' Romans 16:2; Ephesians 5:3. The word agios corresponds with the Hebrew qadosh. The word chasid corresponds more with asios, translated 'holy' in 1 Timothy 2:8; Titus 1:8; Hebrews 7:26; Revelation 15:4; and 'Holy One' in Acts 2:27; Acts 13:35.
As there were many saints on the earth in O.T. times, so we read in the Revelation that there will be saints on the earth after the church has been taken to heaven. Ignorance of this has often led to a mistaken application of the prophecies to the church. Revelation 13:10; Revelation 14:12; Revelation 18:24; Revelation 20:9; etc.