The Shulchan Aruch states that if one cannot keep kavanah during the recital of the silent Amidah, one should at a bare minimum strive to do so during the recitation of the first bracha. Accordingly, I've spent a lot of time on that one bracha. I'd like to tie this in to my previous discussion about imitatio dei.
All translations are from the ArtScroll Nusach Ashkenaz siddur.
The first bracha is about Hashem and his relationships with the founders of our religion - Avraham, Yitzchak, and Yaakov. Hashem is listed as their God both collectively and individually - God of our Fathers, God of Abraham, God of Isaac, God of Jacob. I was taught this was to show that while they all were worshipping the same God, their relationship with Hashem varied by individual. The prayer then goes on to list some of God's attributes. These are listed in ascending order of might and are drawn from the Tanach - the great, mighty, and awesome God, the Supreme God. Having described the solitary might of Hashem, we then talk of Hashem's relationship to the world - Who bestows beneficial kindnesses and creates everything.
Next we describe Hashem's relationship with the founders. What is it that Hashem chooses to remember about our ancestors? Usually we speak of zechut avot the merit of the founders. Surely the Amidah must speak of their devotion and love of Hashem, of their piety and eagerness to serve? Not exactly: - Who recalls the kindness of the Patriarchs. Just as Hashem is described as one Who bestows beneficial kindnesses so what he chooses to remember of our ancestors is that they themselves were kind. And kind to whom? It is not possible to be kind to Hashem, who is complete, perfect, and beyond all needs. Rather what we emphasize in the key prayer of our liturgy is Hashem's remembrance of the excellence of our founders at mitzvot ben adam l'chavero - between man and man.
Once again we see the importance in Judaism of being kind to others. It is because of our founder's kindnesses that we were chosen to be Hashem's Am Segulah - Hashem's treasured people.