If one is asked to carry out a task for another he should try to accomplish it with the best intentions and effort. Provided he is capable of accomplishing the task, it is a worthy cause for a worthy person. All the while trusting in H'shem to help and guide him.
425

Nefesh Hachaim
The meaning of the Gemara that "Prayer is answered only
if he puts his whole soul into it"
refers to one feeling as if his soul is uplifted and attaches to heaven
with every word accompanied by a "burning love of GD"
Gate Two, chapter 14 pg 98