Generally, three methods were used to preserved úódõth:

The first method was memorization. The Arabs were renowned for their memories, particularly their ability to memorize long poems along with the biographies of their authors. They could recollect long lists of the names of poets’ forefathers and their lineages. Not only that, the Arabs also memorized the lineage of their horses, even the horse’s gaits. Thus, thousands of names were at the tip of their tongues, and through the blessings of the ahadith Allah سبحانه وتعالى added to their proficiency in the art of memorization.

This simple method of preserving hadith cannot be ignored, especially when eminent personalities like Imam Bukhari have recorded incidents such as that of Marwan, which illustrate the extraordinary memory of the Arabs. Marwan was the first governor of Damascus and also the first emir of the Umayyad Dynasty.

His secretary, Abu al-Za‘za, narrates that once Marwan called the eminent Sahaba رضي الله عنه‎, Abu Hurairaرضي الله عنه‎ to his court. It is said that the reason behind this rare invitation of a Sahaba رضي الله عنه‎ to Marwan’s court was that Marwan doubted the large number ofahadith Abu Hurairaرضي الله عنه‎ had memorized and frequently narrated. Before Abu Huraira رضي الله عنه‎ entered, Marwan instructed his secretary, Abu al-Za‘za, to hide behind a curtain with a pen and paper in his hand. He said, “I am going to ask him to narrate some ahadtih; while he narrates, I want you to pen all the ahadith down.” When Abu Hurairaرضي الله عنه‎ entered, Marwón asked him about some aúódõth. As Abu Hurairaرضي الله عنه‎began narrating, Abñ al-Za‘za wrote them down. Abu al-Za‘za says, “Abu Hurairaرضي الله عنه‎continued narrating for a long time and I saw that I had written a large collection of aúódõth on my papers.” It seems from Abu al-Za‘za’s words “hadithun kathirun” that he had indeed recorded a large collection of aúódõth on his paper.

Meanwhile, Abu Huraira رضي الله عنه‎had no idea he was being tested. After this, Abu Huraira رضي الله عنه‎left. Marwan preserved the scrolls of the secretly recorded ahadithand waited for the following year. A year later, Marwan again invited Abu Huraira رضي الله عنه‎t o honor him with his presence. Once again, Marwan told Abu al-Za‘za to hide behind the curtain with the papers on which he had written the ahadith the previous year. He said, “I am going to repeat the same questions I asked last year. Check and see if it coincides with the aúódõth of the previous year.” It was an extemporaneous test for Abu Hurairaرضي الله عنه‎. Abu al-Za‘za says, “So Marwan kept the year old ahadith in his hands. After one year, he again called upon Abu Huraira رضي الله عنه‎ as I sat quietly behind the curtain. As he put the questions, I looked into my papers. He did not add to or subtract from even one word of a úadīth.”8

Though it is not possible to ascertain the exact number of ahadith noted, it is clear that it was a significant number. A similar incident occurred with Ibn Shihób al-Zuhrõ during the same time period. Hishóm ibn ‘Abd al-Malik called Ibn Shihób to his court. In this incident, it is clearly mentioned that Ibn Shihób narrated exactly four hundred aúódõth.

It is also mentioned in the books of history that Hishóm tested Ibn Zuhri’s memory as Marwan had Abñ Huraira’s رضي الله عنه‎. The story goes like this:

One day, Ibn Shihab came to the court for something. Hisham personally requested Ibn Shihab to write some ahaadith for his son, the prince. Ibn Shihab accepted; a scribe was called in and the dictation began. Dhahabi writes, “Ibn Shihab dictated four hundred ahdith to the prince.” Then Ibn Shihab left. When Ibn Shihab returned a month later, Hisham feigned remorse by saying to Ibn Shihab, “I am saddened to tell you that the parchments on which the ahadith were written have disappeared and they are nowhere to be found.” “What is this to cry about?” asked Ibn Shihb. “Call the scribe and I will dictate them again.” This was precisely the objective of Hisham. He quickly ordered the scribe to his court. Ibn Shihab dictated the same ahadith over again. The first collection of ahadith had not really disappeared, it was only a ploy to test Ibn Shihab’s memory of ahadith. When Ibn Shihab left the court, Hisham compared the older copy with the new one and saw that no change had been made to the original copy of ahadith.9

Had it not been for the huffaz [memorizers] of Qura’n today, the claim “not one addition had been made to the original copy of ahadith” would seem like a tale from a children’s storybook. Today one can test a hafiz [memorizer] from the Qura’n, which is bigger than a collection of four hundred ahadith. Having him read a chapter of the Qur’an and then asking him to recite it from memory will prove that word for word, there will be no difference between the first recitation and the second. One is thus forced to admit that neither any addition nor any subtraction was made to these ahadith.