This is a class on Tomar Devorah (written by Rav Moshe Cordevero, student of the Arizal). The first chapter discusses Hashem's 13 Attributes of Mercy (the yud-gimmel middos harachamim) and, in a very concrete way, describes what it means for us to emulate them. These attributes are rooted in the highest of all the sefiros, Keter ("crown"). The rest of the book works its way through all the other sefiros, describing the characteristics they represent, and explaining how we can emulate them in our own lives.A major point here is that, as a rule, Hashem treats us measure-for-measure. When we emulate these attributes towards other people in our lives then Hashem, in turn, treats us in the same way. What's more, when we strengthen these attributes within ourselves, it effects the whole world.