When we have the knowledge of the constant presence of God, nothing else is needed.
No matter how depressing or frustrating life becomes, no matter how dull the mind or sick the heart, one has only to think on the Divine Unity, on the oneness of His name, and the way is cleared for joy.
True, an effort of will is needed to concentrate the thought and contemplate God’s unity.
But it is a minimal effort of guiding the mind, and it is less an effort than that which is equivalent to action.
The thought keeps moving, no matter how we feel.
To direct it in a certain way requires a certain amount of preparation beforehand.
We need to have the tools, because it is not only a mental process.
And there are any number of complex soul situations.
Nevertheless, one is almost always compelled to think of oneself.
And the thought “Who am I?” is hardly ever out of range.
Who am I then that I dare to raise my head and share the life of the universe for a single moment?
What am I and what is my life worth?
To this one responds, “My life is nothing, but God is here; He is with me.”
–Rabbi Adin Steinsaltz