Jesus says: “Enter ye in at the strait gate: for wide is the gate, and broad is the way, that leadeth to destruction, and many there be which go in thereat; because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it” (Matthew 7:13–14).
“Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven” (Matthew 7:21).
“For many are called, but few are chosen” (Matthew 22:14).
“The Lord knoweth them that are his” (2 Timothy 2:19). “Now if any man has not the Spirit of Christ, he is none of his” (Romans 8:9).
“Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in you? If any man defile the temple of God, him shall God destroy; for the temple of God is holy, which temple ye are” (1 Corinthians 3:16–17).
“We are of God: he that knoweth God heareth us; he that is not of God heareth not us. Hereby know we the spirit of truth, and the spirit of error” (1 John 4:6).
“Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God. In this the children of God are manifest, and the children of the devil: whosoever doeth not righteousness is not of God, neither he that loveth not his brother” (1John 3:9-10).