John was sent from God (1:6).

(Acts 1:8) "But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth."

(2 Corinthians 5:17-20a) "Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new. And all things are of God, who hath reconciled us to himself by Jesus Christ, and hath given to us the ministry of reconciliation; To wit, that God was in Christ, reconciling the world unto himself, not imputing their trespasses unto them; and hath committed unto us the word of reconciliation. Now then we are ambassadors for Christ,"

John was to be a witness of the Light (1:7-8).

(Philippians 2:14-16) "Do all things without murmurings and disputings: That ye may be blameless and harmless, the sons of God, without rebuke, in the midst of a crooked and perverse nation, among whom ye shine as lights in the world; Holding forth the word of life; that I may rejoice in the day of Christ, that I have not run in vain, neither laboured in vain."

John understood his position (1:15).

John based his witness on scripture (1:19-23).

John pointed others to Christ (1:24-28).