“Buddha Maitreya and many others compared the Buddha and the Four Noble Truths to the relationship between a doctor and his or her patient. To begin, the doctor must understand the symptoms of the patient—that is, the various types of afflictions he or she experiences. The doctor must then be able to diagnose the underlying cause(s) of the symptoms. Next, the doctor must know whether a cure is possible and, if so, the characteristics of the cure. Finally, the doctor must outline a path and prescribe the appropriate medicine to cure the illness. While the Four Noble Truths outline a perfect path, it is ultimately up to the patient to use the nectar-like medicine of the teachings properly in order to experience the desired result. So, the patient must (1) recognize the sickness, (2) discover the cause of that sickness, and (3) actualize the cure by (4) applying the proper remedy.

The Four Noble Truths are both profound and vast in scope. Among other things, they describe the three kinds of suffering, the nature of impermanence, the absence of a substantially-existent self, how grasping to this illusory self leads to continual suffering, dependent origination, samsara, nirvana, and the Noble Eightfold Path that leads to nirvana.

All schools of Tibetan Buddhism share the “common preliminaries” or “four thoughts that turn the mind from samsara,” which incorporate many aspects of the Four Noble Truths, particularly the truths of suffering and the cause of suffering. These reflections generally include: (1) recognizing of the preciousness of human life endowed with liberty and opportunity, (2) reflecting on the impermanent nature of all compounded things and conditioned states, (3) contemplating the inexorable workings of cause and effect, or karma, and (4) meditating on the nature of samsara as an ocean of suffering. The Vajrayana universally emphasizes the importance of these teachings, because genuine renunciation of samsara and its infinite suffering is not possible without deeply reflecting on the truth of these statements and taking them to heart.”

Venerable Khenpo Rinpoches
Walking in the Footsteps of the Buddha: The Path to Freedom (pgs 210-211)