But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus, his Son, purifies us from all sin.
1 John 1:7 (NIV)
If we walk in the light, it will expose some of the darkness of sin in our lives. Thankfully, the blood of Jesus, God's Son, purifies us from all sin. We need to come into the light though.
Jesus is the Light of the world. In Him there is no darkness at all. We need to come to Him.
One of the fruits of fellowship with God is fellowship with His people too. When we get adopted into God's family with Him as our heavenly Father, we get a family of believers who we get to fellowship with. We need to encourage one another to stay in the light.
If we claim to walk in the light but hate a brother or sister, we betray the fact that we don't. Hatred and love are incompatible, like light and darkness, or oil and water. Jesus can cleanse us from our hatred and sinfulness.
'Father God, please illuminate our hearts with the truth of Christ and the purity that comes from trusting in His blood. In His name we pray, amen'.