Mark is the only evangelist who adds the commandment, “Do not defraud.” According to some this is a reflection of the 10th commandment (Do not covet); according to others it is reference to Deuteronomy 24:14 (not to keep from the hired servant his wages), while still others defend the idea that this is not a direct quotation but rather a free summary of all sorts of positively formulated commandments, that one gives to every person what is his.1
19 You know the commandments: ‘Do not murder, Do not commit adultery, Do not steal, Do not bear false witness, Do not defraud, Honor your father and mother.’”