John the Apostle
John 15:10ESV·traditional attribution

If you keep my commandments, you will abide in my love, just as I have kept my Father’s commandments and abide in his love.

John Calvin Reformed @genevareformer

10. If you keep my commandments. He points out to us the method of perseverance. his, to follow where he calls, for, as Paul says, They who are in Christ walk not according to the flesh, but according to the Spirit, (Romans 8:1.) For these two things are continually united, that faith which perceives the undeserved love of Christ toward us, and a good conscience and newness of life.

Matthew Henry Presbyterian @wholebiblehenry

Christ, who is love itself, is here discoursing concerning love, a fourfold love. I. Concerning the Father's love to him; and concerning this he here tells us, 1. That the Father did love him (Joh 15:9): As the Father hath loved me. He loved him as Mediator: This is my beloved Son. He was the Son of his love.

Commenting on John 15:9-17

John Gill Reformed Baptist @doctorgill

These things have I spoken unto you,.... Concerning the vine and branches, his abiding in them, and they in him, their fruitfulness from him, and perseverance in him, his love to them, and theirs to him: that my joy might remain in you; meaning either that joy with which he joyed in and over them, as united to him, and which is of the same...