The Four Noble Truths of Buddhism are succinctly stated by Stephen Batchelor in his Buddhism Without Beliefs:
1. Living is anguish-filled
2. Anguish originates in striving, or craving
3. Anguish can be made to cease
4. A path can be cultivated toward cessation.
So anguish must be acknowledged, then its origins relinquished; with its cessation realized (for the time being), a path might be cultivated toward further cessation.
Or, understanding anguish leads to letting go of craving, which leads to realizing its cessation, which leads to cultivating the path. It’s a circle rather than a series of stages. These are not four separate activities, but four phases within the process of awakening itself.
Understanding matures into letting go; letting go culminates in realization; realization impels cultivation.
The trajectory isn’t a linear sequence of stages through which we “progress“. We never leave behind an earlier stage in order to advance to the next level of some hierarchy. All four activities are part of a single continuum of action. Dharma practice cannot be reduced to any one of these four; it’s configured from them all. When understanding is isolated from letting go, it devolves into mere intellectuality. As soon as letting go is isolated from understanding, it devolves into spiritual posturing. The fabric of Dharma practice is woven from the threads of these interrelated activities, each of which is defined by its relation to the others.