16 Be a lover of poverty, and be desirous of neediness. If you have them both for your portion, you are an inheritor on high. Despise not the voice of the poor and give him not cause to curse you. For if he curse whose palate is bitter, the Lord will hear his petition. If his garments are foul, wash them in water, which freely is bought. Has a poor man entered into your house? God has entered into your house; God dwells within your abode. He, whom you have refreshed from his troubles, from troubles will deliver you. Have you washed the feet of the stranger? You have washed away the filth of your sins. Have you prepared a table before him? Behold God eating [at it], and Christ likewise drinking [at it], and the Holy Spirit resting [on it]: Is the poor satisfied at your table and refreshed? You have satisfied Christ your Lord. He is ready to be your rewarder; in presence of angels and men He will confess you have fed His hunger; He will give thanks unto you that you gave Him drink, and quenched His thirst.
Source: On Admonition and Repentance (New Advent)