What Constitutes the True Practice of Investigation and Realization?

Contemplate the Dharma requiring investigative realization within meditative concentration; the deeper the concentration, the better. Forget all surroundings, leaving only the meaning of the Dharma—devoid of words, language, or sound—within the mind. There should be only profound doubt, profound contemplation, seemingly inquiring yet not inquiring, seemingly thinking yet not thinking, continuously abiding without separation, present yet as if absent, vague and elusive—unable to be grasped nor discarded. By diligently practicing this way, realization is an inevitable outcome. It is crucial never to mistake mere thinking devoid of meditative concentration for contemplative practice, nor to regard the shallow results of mental deliberation as genuine realization.