“So long, monks, as my knowledge and vision of these Four Noble Truths as they really are … was not thoroughly purified in this way, I did not claim to have awakened to the unsurpassed perfect enlightenment,” the Buddha said in his first discourse. This utterance tells us that, contrary to popular belief, the Four Noble Truths are far from introductory teachings of Buddhism, for to fully understand them is to attain enlightenment.
The four noble truths are reminiscent of a medical formula, and the Buddha himself is compared to a great physician. Just as the doctor diagnoses the patient and prescribes the medicine, the Buddha pinpoints humanity’s ailment and prescribes the treatment to overcome it.
As such, the first noble truth diagnoses the affliction, the second noble truth reveals its origin, the third noble truth points to the cure, and the fourth noble truth shows the way to the cure.
This is how the Buddha defined the First Noble Truth of suffering (dukkha):
Now this, monks, is the noble truth of suffering: birth is suffering, aging is suffering, illness is suffering, death is suffering; union with what is displeasing is suffering; separation from what is pleasing is suffering; not to get what one wants is suffering; in brief, the five aggregates subject to clinging are suffering. ~ In the Buddha’s Words
Here’s a wonderful talk given by Ven. Bikkhu Bodhi’s on the First Noble Truth:

From the Buddha’s definition of the First Noble Truth, we can discern three aspects of dukkha (suffering): the physical suffering, the psychological suffering, and existential suffering (the five aggregates of attachment).
The first aspect of dukkha is defined in this way, “Birth is suffering, aging is suffering, illness is suffering, death is suffering.” As you can see, all four elements correspond to the suffering of the physical body, which starts at the moment of birth and ends with death. We might not remember it, but our birth was a painful process not just for our mothers but also for us. We were expelled from the womb into the world, helpless, against our will, and forced to go through all the stages of life. Next comes aging, when our skin becomes wrinkled while our physical and mental faculties start to whither away. As our bodies are weakened, they become susceptible to many illnesses that inevitably lead to death and the body’s complete dissolution.
The second aspect of dukkha is contained in this line, “Union with what is displeasing is suffering; separation from what is pleasing is suffering; not to get what one wants is suffering.” This is the psychological suffering that we are bound to experience throughout the course of our entire life. As we’re forced to associate with unpleasant people, get into stressful situations, lose our loved ones, and fail to attain the things we desire. All of these are the inevitable and intrinsic part of everyone’s journey and can’t be avoided.
The third aspect of dukkha is by far the hardest to comprehend because it’s defined using the term “five aggregates of attachment.” This one phrase encompasses the Buddha’s teaching on the false sense of fixed identity that we believe to be our true “self.” The Buddha teaches us that this self consists of five components (aggregates): body, feelings, perceptions, volitions, and consciousness. These aggregates are anything but stable and undergo a constant process of arising and fading away every moment. To be attached to these changing processes and seek your “self” in them is the most basic delusion that serves as the source of our unhappiness and discontent.
Thank you so much
Sādhu Sādhu Sādhu 🙏🙏🙏
Hi Laytin, thank you for the kind words. 🙏