For I [Gd] have known him [Avraham], to the end that he may command his children and his household after him, that they may keep the way of Gd, to do what is just (צדקה) and right (משפט) so that Gd will give to Avraham that which [Gd] promised. (Genesis 18:19).
On the use and order of the wordsצדקה followed byמשפט, Rabbi Yehuda taught: that which starts with justice will end in ethical appropriateness as exemplified by how Avraham would receive wayfarers. After they had eaten and drunk, he would say to them “Bentsch 'Blessed are you Gd of the world of whose food we have eaten.'” If the traveler would bentsch he could eat and then leave; if he refused, Avraham would reply “Pay what you owe me.” “How much do I owe you?” the traveler would ask. Avraham would reply, “A flask of wine X, a pound of meat Y, a loaf of bread Z – who do you suppose is giving you wine, meat and bread in the wilderness?” The wayfarer, now aware that he must either pay or thank Gd would then say, “Blessed are you Gd of the world of whose food we have eaten.” Thus, Avraham exemplified that when one acts justly the morally right outcome will prevail.
