John 1:20 - Matthew Poole's English Annotations on the Holy Bible

And he confessed; he being asked openly and plainly, professed, and denied not; and did not dissemble nor halt in his speech. These negatives are in Scripture often added to affirmatives, to exclude all exceptions, Job 5:17 Psalms 40:10-12. But confessed: he did not tell them once so, but again and again, because many were musing about it, Luke 3:15. I am not the Christ; I am not that great Messiah which God hath promised you, and in the expectation of whom you live, Luke 2:26,38 Lu 19:11 1 Thessalonians 4:25. The diligence we shall constantly observe in the servants of God in holy writ, to avoid the arrogating of that honour to themselves which is due only to God and Christ; and this, together with John's steadiness and plainness, doth very well become all professors, but the ministers of the gospel especially.