Saint Thomas Aquinas says, wisely, that the only way to drive out a bad passion is by a stronger good passion. The same is true of thoughts as of passions. When your mind wanders, like a child, your will must bring it back, like a mother. [. . .] The will-parent must discipline the mind-child, avoiding both the opposite extremes commonly made in disciplining either children or thoughts: tyranny or permissiveness.
If we rely on anything else besides faith to maintain the practice of the presence of God, we will certainly fail, whether this is our feelings, or experiences, or sincerity, or good intentions, or reasonings, or plans. The reason these things will fail while faith will not fail is that all these things depend on us, while faith depends on God. It is a gift of God.