“This then is the message which we have heard of him, and declare unto you, that God is light, and in him is no darkness at all.”
1 John 1:5

God is light and in him is no darkness at all, there is no sin or confusion in him. In God, you’d always have direction, guidance and clarity.
So he says:
“If we say that we have fellowship with him, and walk in darkness, we lie, and do not the truth:” 1 John 1:6
In other words, if we fellowship with him, for certain we would never walk in darkness, this is his pledge to us- he assures us, that if we fellowship with his word, there would be no confusion, uncertainty, pain, lack and darkness in our lives, exactly what Jesus said:
“…I am the light of the world: he that followeth me shall not walk in darkness, but shall have the light of life.” John 8:12
And how true! Those who walked with Jesus eventually figured that following him ensured they never walked in darkness: they were provided with direction and resources at every given moment:
“And he said unto them, When I sent you without purse, and scrip, and shoes, lacked ye any thing? And they said, Nothing.” Luke 22:35

Bible Reading Plan: Genesis 38, Mark 10