Knowing the exact nature of everything, God permits each person to be tested according to his strength. As St. Paul puts it: 'God is to be trusted not to let you be tried beyond your strength, but with the trial He will provide a way out, so that you are able to bear it' (1 Cor. 10:13).
When tested by some trial you should try to find out not why or through whom it came, but only how to endure it gratefully, without distress or rancor.
If you wish that God should speedily give you hearty faith in prayer, strive with all your heart to speak and to do everything in regard to other people sincerely, and never be deceitful in your dealings with them. If you are straightforward and truthful with others, then God will give you straightforwardness and sincere faith also in reference to Himself.