Jamieson, Fausset and Brown on Luke 7:40-43

40-43. Like Nathan with David, our Lord conceals His home thrust under the veil of a parable, and makes His host himself pronounce upon the case. The two debtors are the woman and Simon; the criminality of the one was ten times that of the other (in the proportion of "five hundred" to "fifty"); but both being equally insolvent, both are with equal frankness forgiven; and Simon is made to own that the greatest debtor to forgiving mercy will cling to her Divine Benefactor with the deepest gratitude. Does our Lord then admit that Simon was a forgiving man? Let us see.