1 John 5:8

Verse 8. And there are three that give testimony on earth: the Spirit, the water, and the blood; and these three are one. [3] This is a repetition of what was before said, verse 6, to be expounded in the same manner. But when it is added, these three are one, the sense is, that they witness one and the same truth. Witham.—As the Father, the Word, and the Holy Ghost, all bear witness to Christ’s divinity; so the spirit, which he yielded up, crying out with a loud voice upon the cross, and the water and blood that issued from his side, bear witness to his humanity, and are one; that is, all agree in one testimony. Challoner.