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).
It is pointless for someone to say that he has faith in God if he does not have works which go with faith. What benefit were their lamps to the foolish virgins who had no oil (Matt. 25: 1-13), namely, deeds of love and compassion?
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.