The first lesson a poor sinner has to learn is to trust in the Lord with all his heart, and not in his own understanding; to trust God not only for what he does understand and for what is explained, but also for what he does not understand and for what is not explained.
This is faith. Such faith honors God and saves the soul. This is receiving the kingdom of God as a little child, who always believes that things must be right if one he loves and trusts says them.