Friends:

 

How is the Mutual Co-Dependence of Faith?

Having faith, an effort is made! By making an effort, faith arises!
Having faith, awareness is setup! By setup awareness, faith arises!
Having faith focuses concentration! By concentration faith arises!
Having faith one understands! One who understands gains faith!
Having faith it is exerted; because it is exerted it gathers faith...
Having faith it is established; by being established it makes faith...
Having faith it is concentrated; being concentrated it reaps faith...
Having faith it understands; because it understands it earns faith...

Source: Sariputta - The General of the Dhamma -
The Canonical: Path of Discrimination: Patisambhidamagga. IV.
http://www.pariyatti.com/book.cgi?prod_id=133494

For fine further Faith (Saddhā)  please see:
http://What-Buddha-Said.net/drops/III/Going_Forth_Faith.htm
http://What-Buddha-Said.net/drops/III/Outstanding_Faith.htm
http://What-Buddha-Said.net/drops/III/Unwavering_Faith.htm
http://What-Buddha-Said.net/drops/III/Analysis_of_Faith.htm
http://What-Buddha-Said.net/drops/III/Power_of_Faith.htm
http://What-Buddha-Said.net/drops/III/Faith_Summary.htm
http://What-Buddha-Said.net/drops/III/Highest_Faith.htm
http://What-Buddha-Said.net/drops/III/Fruitful_Faith.htm
http://What-Buddha-Said.net/drops/III/Leaping_Faith.htm
http://What-Buddha-Said.net/drops/III/Mutual_Faith.htm
http://What-Buddha-Said.net/drops/III/Dual_Faith.htm
http://What-Buddha-Said.net/drops/III/Fine_Faith.htm
http://What-Buddha-Said.net/drops/III/Rich_Faith.htm
http://What-Buddha-Said.net/drops/III/Lay_Faith.htm