This is the only way to still the mind. To hold fast to one thought. Practice if you like with holding one's thought on the flame of a candle or the breath. Use these practices in discipline to ready you for holding your attention within your own Awareness aka Soul.
Holding one's attention in Awareness will feel like an odd and uncomfortable experience at first as Awareness is not an object but an activity.
Awareness is the activity of Consciousness or you could say that Soul (Awareness) is the activity of Spirit (Consciousness).
The mind being the vessel of Consciousness (conscious mind) and Awareness (subconscious mind/present moment) one must be empty of all egoic thoughts while resting in peace (meditation aka a singular thought). Only in this manner can the two I am's align with one another. Only in this manner can one's true Consciousness merge with the conscious of mind.
~ Tracy Pierce