Faithful Witness
In Revelation 1:5; 3:14, the faithful witness signifies that the Lord is Divine Truth itself, and the Lord as the Word, which is divine truth from Him. (Apocalypse Revealed 16, 199, Apocalypse Explained 226)
Revelation 1:5
5
and from Jesus Christ, the faithful witness, the firstborn of the dead, and the ruler of the kings of the earth. To him who loves us, and washed us from our sins by his blood;