ספר בראשית

Genesis 32,28. “He said: ‘your name will no longer be ‎Yaakov, but Israel, for you have contended both with celestial ‎forces and with human forces and you have prevailed.’” ‎There are people who constantly remain attached to G’d even ‎while they are engaged in conversation with human beings. There ‎are other people, who while engaged in a conscious effort to serve ‎the Lord, concentrate on this to the exclusion of everything else; ‎these people while engaged in mundane activities, such as ‎business conversations with their peers, cannot at the same time ‎remain conscious of their duties towards their Creator. The first ‎type of person deserves the title: “Israel;” as the letters ‎ישר‎, ‎‎“upright,” as well as the letters ‎ראש‎, “head,” are part of that title. ‎The second category of person, (observant Jew) is called ‎יעקב‎, i.e. ‎י-עקב‎, meaning that his attachment to G’d is ‎עקב‎, “secondary,” ‎just as a heel is a secondary and not a primary organ. Esau’s ‎celestial representative acknowledged that Yaakov was a person ‎for the first category, since in his dealings with man he never lost ‎sight of his primary duties to his G’d.‎