In Jesus, God glorifies Himself. It is a strange thought that the supreme glory of God lies in the incarnation and the cross. There is no glory like that of being loved. Had God remained aloof and majestic, serene and unmoved, untouched by any sorrow and unhurt by any pain, men and women might have feared Him and they might have admired Him; but they would never have loved Him. The law of sacrifice is not only a law of earth; it is a law of heaven and earth. It is in the incarnation and the cross that God’s supreme glory is revealed.
– William Barclay, Commentary on John 13:31-32