The most likely author of John 13:34-35 is the apostle John, who is traditionally identified as the author of the Gospel of John. John was one of Jesus’ original disciples and was known as the “disciple whom Jesus loved.” He was a close companion of Jesus and was present at many key moments in Jesus’ life and ministry.

From an evangelical Christian perspective, John is seen as a faithful and reliable witness to the life, teachings, death, and resurrection of Jesus Christ. His Gospel is often considered to be a highly theological and spiritual account of Jesus’ life, highlighting the divinity of Christ and the importance of faith in him for salvation.

In John 13:34-35, Jesus gives his disciples a new commandment to love one another as he has loved them. This commandment is central to the Christian faith and is viewed as a defining characteristic of a true follower of Jesus. Evangelical Christians believe that this love should extend not only to fellow believers but also to the world at large, as a witness to the transformative power of the gospel.

Overall, the authorship of John 13:34-35 by the apostle John is significant for evangelical Christians, as it is a foundational passage that emphasizes the primacy of love in the life of a Christian and reflects the teachings and character of Jesus Christ.