John 1:34 (NIV) - "I have seen and I testify that this is the Son of God."
John knew without a doubt who Jesus was.
He witnessed God's Spirit descend on Him and he heard God's voice affirming that Jesus was indeed His Son, the promised Messiah. John then testified as a witness of these things to all who would listen.
It was his honor and privilege to see God's Son and he acknowledged Him often. When asked, he freely and openly stated that Jesus was sent from God.
John urged those who had been following him to put their trust in Jesus instead. He stated "Whoever believes in the Son has eternal life, but whoever rejects the Son will not see life, for God's wrath remains on him." (John 3:36-NIV)
Humbly and willingly John accepted his task of pointing others to Jesus. He openly declared that Jesus was the Son of God, the long-awaited Messiah, the one sent by God to redeem Israel and the whole world.
As His followers we have seen Him too, we have been redeemed, we have heard and responded to His voice entreating us to "Follow Me."
Like John, it is our honor and privilege to speak of Him often and point others to Him. We witness all He has done and is doing in our lives then humbly and willingly we testify to all who will listen.