He confessed (admitted the truth) and did not try to conceal it, but acknowledged, I am not the Christ!
He was not the Light himself, but came that he might bear witness regarding the Light.
And as John was ending his course, he asked, What or who do you secretly think that I am? I am not He [the Christ. No], but note that after me One is coming, the sandals of Whose feet I am not worthy to untie!