A statement or other evidence that something is true; a testimony. A witness can also be someone who gives such a statement or evidence based on personal knowledge; that is, someone who bears testimony.

Thou shalt not bear false witness, Ex. 20: 16. The gospel will be preached in all the world for a witness unto all nations, Matt. 24: 14 (JS-M 1: 31). Ye shall be witnesses unto me, Acts 1: 8. The Spirit itself beareth witness with our spirit, Rom. 8: 16 (1 Jn. 5: 6). Ye are willing to stand as witnesses of God at all times, Mosiah 18: 8-9. We partake of the sacrament to witness unto the Father that we will keep the commandments and always remember Jesus, 3 Ne. 18: 10-11 (Moro. 4, 5; D&C 20: 77-79). We receive no witness until after the trial of your faith, Ether 12: 6. Law of witnesses: in the mouth of two or three witnesses shall every word be established, D&C 6: 28 (Deut. 17: 6; Matt. 18: 16; 2 Cor. 13: 1; Ether 5: 4; D&C 128: 3). I have ordained you to be Apostles and especial witnesses of my name, D&C 27: 12 (D&C 107: 23). The Seventy are called to be especial witnesses unto the Gentiles and in all the world, D&C 107: 25. Let there be a recorder, and let him be eye-witness of your baptisms, D&C 127: 6 (D&C 128: 2-4).