Scripture expressly commands this (Matt. 28:19) and further states that many who do not come are nevertheless called (Matt. 22:14; Luke 14:16–18). They reject the gospel (John 3:36; Acts 13:46; 2 Thess. 1:8) and are therefore guilty of the appalling sin of unbelief (Matt. 10:15; 11:22, 24; John 3:36; 16:8–9; 2 Thess. 1:8; 1 John 5:10).
(A)ll humans are the same by nature, worthy of condemnation before God (Rom. 3:9–19; 5:12; 9:21; 11:32), dead in sins and trespasses (Eph. 2:2–3), darkened in their understanding (1 Cor. 2:14; Eph. 4:18; 5:8). They cannot see the kingdom of God (John 3:3), are the slaves of sin (8:34; Rom. 6:20), enemies of God (8:7; Col. 1:21), do not and cannot submit to God’s law (Rom. 8:7), are unable to think or do anything good from within themselves (John 15:5; 2 Cor. 3:5); though the gospel is for the benefit of humans, they are hostile toward it and despise it as an offense or folly (1 Cor. 1:23; 2:14). Hence the difference that occurs among people after the calling is inexplicable in terms of human capacities. God and his grace alone make the difference (1 Cor. 4:7).
For God no door is locked, no creature unapproachable, no heart inaccessible.