By the time he turned eighteen, al-Bukhārī had already stepped into the world of writing. His first work was a compilation that brought together the intellectual insights of the Prophet ﷺ’s companions and their followers. The book bore a long but meaningful title: Khalaayā aṣ-Ṣaḥābati wa’t-Tābiʿīn wa-Akhbārihim—a record of the noble companions (ṣaḥāba), the followers who learned directly from them (tābiʿīn), and their successors. In this, young Bukhārī affirmed a foundational truth: that the sanctity of Islam had been transmitted as a lived, practiced tradition—from the Prophet ﷺ, heart to heart, generation to generation. His debut work was born out of this reverence for continuity.

At eighteen, then, his thinking already glowed with clarity and depth.

The book was written in Madinah. Those were years of scarcity, of quiet determination. He had no lamp to light his pages. Instead, he wrote under the borrowed glow of the moon that poured through the window of his modest room.

Soon after, his second book appeared—al-Tārīkh al-Kabīr—“The Great History.” It was no mere chronicle, but a monumental biographical encyclopedia of the narrators of hadith, tracing the human chains through which sacred knowledge passed. Al-Bukhārī had realized something many missed: to preserve hadith with integrity, one had to preserve the lives of those who carried it. Truth can only flow through those who live in truth.

He once said, “I had gathered a great number of historical records related to the major transmitters of hadith. But I left many out, fearing the book would become unbearably long.”

His teacher, Isḥāq ibn Rāhawayh, called this book “a colossal remembrance.” Bukhārī never released any of his writings without reviewing them three times—writing, checking, and rewriting. “Every word I wrote,” he used to say, “was written three times.”

Hard work was his mark—unyielding, relentless. Muḥammad ibn Yūsuf al-Bukhārī recalled a night when the Imam woke up not once, but eighteen times. Each time, he rose from his bed, lit the lamp, and scribbled down flashes of insight related to hadith. Even during travel, the writing did not stop. Again and again, he would get up in the dark, ignite a lamp, and write down whatever came to his heart.

There was a particular joy he found in the pursuit of knowledge. He spent all he had—every coin, every resource—for it. It came to a point where he even sold his clothes. ʿUmar ibn Ḥafṣ al-Ashkar once said:

“While we were in Basra studying hadith, Bukhārī suddenly disappeared. Days passed. We searched and finally found him inside his home, without even a proper garment to wear. He had exhausted everything he owned. He had no suitable clothes to step outside. We gathered some money, bought him decent clothing, and gave it to him.”

There were times when al-Bukhārī had nothing to eat but leaves. On one occasion, he spent three days this way. On the third day, a stranger came and handed him a small pouch of dinars, saying, “Use this for your needs.”

“I used to earn 500 dirhams a month,” Bukhārī once said, “but I spent all of it on the pursuit of knowledge. Eventually, I was left with nothing.”

While writing his tafsir—his commentary on the Qur’an—there were nights when he collapsed from exhaustion, lying on the ground, unable to move.

His intelligence was extraordinary. His memory, nothing short of miraculous. It’s said he memorized seventy thousand hadiths in one sitting. One glance at a book was often enough for him to internalize its entire content.

He once recalled, “When I reached Balkh, they asked me to hand over what I had written. Instead, I recited to them a thousand hadiths from memory—every one of them exactly as I had recorded it from my thousand teachers.”

His contemporaries recognized his brilliance. In the school at Marw, a senior scholar once asked him, “Boy, how many hadiths have you written down?” When Bukhārī answered, two fellow students laughed. But the teacher silenced them: “Don’t laugh. One day, he will amaze you all.”

And the teacher’s words came true.

Ibn Khuzaymah said of him, “Under the sky, I have not seen anyone more learned in hadith than Bukhārī.”

Imām Muslim called him “the leader of the scholars of hadith.”

In Khurāsān, when he would teach, up to twenty thousand people would gather. In Naysabūr, his arrival was marked by a procession of four thousand horsemen. Some rode mules. Others came on camels. People came from far and wide, crossing rivers and deserts, just to sit in his presence.

Such was the magnetic pull of his light. A man who once lost his sight as a boy, now illuminating the world with the light of knowledge that burns across centuries.