Jamieson, Fausset and Brown on 1 John 3:16

16. What true love to the brethren is, illustrated by the love of Christ to us.

Hereby--Greek, "Herein."

the love of God--The words "of God" are not in the original. Translate, "We arrive at the knowledge of love"; we apprehend what true love is.

he--Christ.

and we--on our part, if absolutely needed for the glory of God, the good of the Church, or the salvation of a brother.

lives--Christ alone laid down His one life for us all; we ought to lay down our lives severally for the lives of the brethren; if not actually, at least virtually, by giving our time, care, labors, prayers, substance: Non nobis, sed omnibus. Our life ought not to be dearer to us than God's own Son was to Him. The apostles and martyrs acted on this principle.