There is no reason, then for us to exempt any covetings, however light, from the judgment of death. Augustine says: In weighing sins “let us not bring forward false balances to weigh what we please and as we please, according to our own opinion, saying ‘This is heavy’; ‘This is light.’ But let us bring forward the divine balance of the Holy Scriptures as from the Lord’s treasury, an in that balance let us weight what is heavier. No — not weigh; rather, let us recognize what the Lord has already weighed.”
–John Calvin, The Institutes of the Christian Religion, vol 1. (ed. Lewis/Battles; Philadelphia, PA: Westminster, 1559), II.ix.58; pg. 422.