Moffatt(i)
16 We know what love is by this, that He laid down his life for us; so we ought to lay down our lives for the brotherhood.
17 But whoever possesses this world's goods, and notices his brother in need, and shuts his heart against him, how can love to God remain in him?
18 My dear children, let us put our love not into words or into talk but into deeds, and make it real.
19 Thus it is that we may be sure we belong to the truth and reassure ourselves