Again Jesus repeated the absolute importance of His disciples loving one another (cf. John 13:34; John 15:10; John 15:12; John 15:14). This was not only a repetition for emphasis, but it set the stage for Jesus" teaching on the world"s opposition that follows. [source][source][source]
Context Summary
John 15:17-27 - Suffering For Jesus' Sake
We have been appointed for the one purpose of bearing imperishable fruit, but our holy service to the world will never be appreciated. The world has its own god and religion. It hates without cause. The more Christlike we are, the closer we shall be identified with His sufferings. There is no limit to the hatred and persecution which the world will vent on those who have ceased to belong to it because of their identification with the Crucified. But through the pitiless storm, we must be glad; there must be no slackening of our love, which will as certainly conquer hate as tomorrow's sun the darkness, John 15:26-27. In each Christian century there has been this double witness of the Spirit in the Church. The voice of the Church has testified to the living Christ, not arguing but attesting; and to each word of testimony the Holy Spirit has borne assenting witness. Christian apologetics are of less importance than the witness of obscure but Spirit-led lives. [source]
Chapter Summary: John 15
1The union of Jesus and his members shown under the parable of a vine 18The hatred of the world 26The office of the Holy Spirit
Greek Commentary for John 15:17
Repetition of John 13:34; John 15:12. This very night the disciples had been guilty of jealousy and wrangling (Luke 22:24; John 13:5, John 13:15). [source]
All my teachings are to the end that you should love one another. [source]