This PhD degree has been the greatest austerity I've ever undertaken. It was often frustrating, demotivating, felt like it would never end, caused my body to frequently fall ill and resulted in a huge amount of worry and pain.
However, the austerity of this PhD have been child's play compared with what a sage named Markandeya Rsi went through. (His story is told in the 12th Canto of the Srimad Bhagavatam. I'm recalling it in my own words here):
Markandeya was meditating on the Supreme Personality of Godhead in his small heritage for many years. He was very strictly and sincerely meditating. So much so, in fact, that Indra, the King of Heaven (aka Zeus), became worried that this Markandeya might become eligible to take over his position soon. Indra therefore sent a team of people to break Markandeya's meditation.
He sent Cupid along with the best of the heavenly singers (Gandharvas), the most beautiful of the heavenly exotic dancers (Apsaras), the season of spring, a gentle cool breeze, intoxication personified and greed personified (the mode of passion and the false ego of thinking in terms of "I" and "mine"). A celebrate monk's worst nightmare. All these together were to create a situation where Markandeya would be tempted to stop his meditation and enjoy materially.
However, faced with these allurements, Markandeya wasn't even slightly shaken. He remained completely steady and fixed in his worship.
Markandeya Rsi's austerities were so powerful, in fact, that the members of Indra's assault team began to burn-up within (similar to what happen when Kapila Muni was attacked by the sons of Sagara who thought he had stolen a sacrificial horse).
Eventually, while Markandeya was meditating in this way, the Nara-Narayana avatar came and visited him. Markandeya immediately recognized the Supreme Lord and worshiped him with expert poetry.
The sage explained: Krishna is like a spider, He creates everything within the universe like a spider creates his web, and then He retracts it all back within Himself. Through Krishna one can conquer material misery, death and even time itself. Time is so powerful that even Lord Brahma (the oldest and most intelligent person in the universe) fears it, but Krishna's devotee need not fear time. The devotee knows that his self is not the body. The modes of nature generally bind us to the material world, but the devotee knows how to use the mode of goodness as a launch pad to blast himself off on a trajectory back to Godhead. Because of their perverted and sinful activities, materialists cannot understand Krishna. So material philosophers therefore come up with so many different theories, doctrines and religions. These are created to match their particular mix of the modes of nature (satva-, raja- and tama-guna), but have no real substance.
After hearing this nice prayer by Markandeya, Nara-Narayana offered him any benediction he might desire. The sage answered that just seeing his worshipable Lord was all he desired. He could imagine no greater gift. However, he was curious about the illusory energy (maya). He asked to understand how it could bewilder so many people into thinking material life was the one true reality.
The Lord ruefully promised to fulfill his wish and then disappeared.
Markandeya went on meditating for a few years when suddenly strong wind started to blow. Soon after, it started raining very heavily. The intense rains caused severe flooding. This hurricane went on continuously for many years. The intense weather eventually caused the entire surface of the earth to become flooded. Practically all species died off in this intense atmosphere. Gigantic sharks roamed the wild waters. The flooding even spread to the higher-dimensional space of the heavenly planets. It was the devastation at the end of the day of Brahma.
Markandeya was swimming and drifting throughout all of this. He lost all sense of orientation, he felt intense hunger and thirst, he got attacked by sharks, he felt extreme pain from various injuries, he was completely exhausted continuously fighting for his life, he frequently fell ill, he felt lamentation, happiness (when he temporarily escaped some danger), fear and misery. This went on for many, many years, all throughout the night of Brahma (4.32 billion years).
After an extremely long time drifting in the waters of devastation, Markandeya spotted a small island with a banyan tree growing on it. In one corner of the tree he saw a young child. As he swam closer to the island he noticed the wonderful beauty of the child. He noted his blackish-blue skin, wonderful jewelry, shark-shaped earrings, auspicious bodily markings and nice cosmetic decorations.
Then, suddenly, the child inhaled and began to suck everything surrounding him into his mouth. Markandeya also got sucked into the mouth of this wondrous child. Within the mouth he saw his old hermitage, the waters of devastation, the heavenly planets, the creation and destruction of the universe, everything, the entire universal manifestation; he even saw time itself, past, present and future, all at once. The child then exhaled and Markandeya found himself spat out back into the waters of devastation.
As he once again began to struggle to keep his head above the waters, he suddenly found himself transported back to his old heritage, as if nothing had happened. He then realized: "oh ... so this is the power of the illusory energy!".
And I realize: a PhD is nothing compared to that.