For where your treasure is, there will your heart be also.
All Commentaries on Matthew 6:21 Go To Matthew 6
Rabanus Maurus
AD 856
Ap. Anselm: Here are three precepts according to the three different kinds of wealth. Metals are destroyed by rust, clothes by moth; but as there are other things which fear neither rust nor moth, as precious stones, He therefore namesa common damage, that by thieves, who may rob wealth of all kinds.
Allegorically; Rust denotes pride which obscures the brightness of virtue. Moth which privily eats out garments, is jealousy which frets into good intention, and destroys the bond of unity. Thieves denote heretics and demons, who are ever on the watch to rob men of their spiritual treasure.