Two of the three deceivers of mankind are encompassed in the word “flesh” as used by St. Paul today (Romans 8:12) – they are the world and our own actual flesh. We should use material goods as a means to an end, tools for getting us to Heaven. So why does Holy Mother church put these two readings together today in this Mass – “Be not debtors to the flesh” (Romans 8:12-17) and the “Children of Mammon” (Luke 16 1-9)? Because our Lord’s point is the same thing in the parable today – to use our material goods wisely.
‘Make friends with the mammon of iniquity’ means use your material treasures, especially your ill-gotten gains or that which is an occasion of sin, to make friends with those who will save your soul. Thus the Counsel of the Catechism of Trent holds out for our moral lesson today the church’s teaching on restitution.