St. Augustine of Hippo (AD 354-430) from the City of God (Book I, Chapter 10)

They lost all they had [in the sack of Rome]. Their faith?
Their godliness? The possessions of the hidden man of the heart,
which in the sight of God are of great price? Did they lose
these? For these are the wealth of Christians, to whom the wealthy
apostle said, "Godliness with contentment is great gain. For we
brought nothing into this world, find it is certain we can carry
nothing out. And having food and raiment, let us be therewith
content. But they that will be rich fall into temptation and a
snare, and into many foolish and hurtful lusts, which drown men in
destruction and perdition. For the love of money is the root of all
evil; which, while some coveted after, they have erred from the
faith, and pierced themselves through with many sorrows."

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