We have come to know by personal observation and experience, and have believed with deep, consistent faith the love which God has for us. God is love, and the one who abides in love abides in God, and God abides continually in him. 1 John 4:16
To abide in God is to abide in His love. It impossible to claim to love God but not love others. If we claim to know God and follow Jesus Christ then our lives should be transformed.
John was an eye witnesses of Jesus Christ. He walked with Jesus during His earthly ministry and John even stated in his gospel that if all the miracles Jesus performed were recorded, there would not be enough books to contain them.
In everything Jesus did He did because of His love and compassion. To know Jesus is to know love. There is no greater love than the love Jesus has for us. As we come to know Him and His love, we are transformed and changed for eternity.