There are two sub-paragraphs in this paragraph: 7-8; 9-11. Verses 7-8 provide the grounds or basis for the appeal in vv. 9-10, followed by a further ground or basis for the appeal in v. 11. Thus, the sermon can arranged in two parts:
A. Because Love: the new commandment – (7–8).
I. Loving fellow believers is how we walk in the light of the Gospel – (vv. 9–11).
In verses 9-11, John makes the point that our response toward other people is evidence of our Christian character. One of the evidences for knowing you’re a genuine Christian is whether you have love for fellow Christians. Notice the tense of the verb hate is present and suggests habitual action. The tense of the verb is very important at this point. John is describing someone whose settled disposition and conduct is one of hatred toward his fellow believers.
In verse 10, John makes the first reference to one of the fundamental virtues of the Christian life: love. John says two things about the one who loves.
First, he abides in the light. He is not only enlightened by the gospel and thus a true Christian, but he obeys the command of Jesus to love others and thus he abides continually in the light.
Second, in such a Christian there is no cause for stumbling. That could be understood in two ways. It can mean because we walk in the light we don’t stumble ourselves. There could be a second meaning here. When you begin to hate others, you cause them to stumble. Simply put, John says in verse 10 that living in the light means loving your brother.
In verse 11, John says three things are true concerning those who hate a brother. First, they are in the darkness. Second, they walk in the darkness. Character brings about conduct. People do what they do because they are what they are. Third, they are without direction in their life (11). Hatred so zaps purpose and direction in life that you can’t know God’s direction for your life.
Hatred takes you out of God’s will for your life. You cannot be in God’s will and hate your brother. So John says he is writing a new commandment: love fellow believers. Jesus is our example.