Mitzvah as Commission

The other day I listened to a podcast of a pucblic lecture from the Jewish Theological Society about translating the Psalms.  One of the speakers was the bible scholar Stephen Geller.  One thing that really stuck with me is that he said that we should not translate the Hebrew word mitzvah as "commandment" but as "commision."  I think the word "commission" gives the idea of mitzvah as a holy undertaking in partnership with God, rather than just following orders from a hierarchical master.