9 Give me a man who has given ear to Christ, give me a man who has heard with fear “Beware of all covetousness;” and let him not say to me, “I am a poor man, a plebeian of mean estate, one of the common people, how can I hope ever to be a judge? I am in no fear of this temptation, the peril of which you have placed before my eyes.” Yet lo, even this poor man I will tell what he ought to fear. Some rich and powerful person calls you to give false witness for him. What will you be doing now?
Tell me. You have a good little property of your own; you have laboured for it, hast acquired, and kept it. That person requires of you; “Give false witness for me, and I will give you so and so much.” Thou who seekest not the things of others, sayest, “That be far from me: I do not seek for what it has not pleased God to give me, I will not receive it; depart from me.” “Have you no wish to receive what I give? I will take away what you have already.” See now prove yourself, question now your own self.
Why do you look at me? Look inward on your own self, look at your own self within, examine your own self within; sit down before your own self, and summon your own self before you, and stretch yourself upon the rack of God's commandment, and torment yourself with His fear, and deal not softly with yourself; answer your own self. Lo, if any one were to threaten you with this, what would you do? “I will take away from you what with so great labour you have acquired, if you will not give false witness for me.”
Give him that; “Beware of all covetousness.” “O my servant,” He will say to you, “whom I have redeemed and made free, whom from a servant I have adopted to be a brother, whom I have set as a member in My Body, give ear to Me: He may take away what you have acquired, Me he shall not take away from you. Are you keeping your own goods, that you may not perish? What, have I not said unto you, 'Beware of all covetousness'?”
Source: Sermons on Selected Lessons of the New Testament (New Advent)