There are several early Islamic inscriptions which mention some of the Prophet's Companions. Let's take a look at some of the inscriptions which can be dated to the 1st century AH.

1. Umar b. Al-Khattab The 2nd caliph, Umar, is mentioned in an inscription dated to 24 AH. The author, Zuhayr, states that he wrote it at the time of Umar's death.

Umar is also mentioned in inscriptions written by his descendants. Two of these, written by his great-grandson Rabah b. Hafs b. Asim b. Umar, are dated to the years 96 and 100 AH. The latter inscription seems refer to him using his title al-Fārūq.

2. Uthman b. Affan The 3rd caliph Uthman is mentioned in an inscription dated to the year 24 AH. It reads: "I am Zuhayr. I have believed in Allah. And I wrote it at the time Ibn Affan was made commander in the year 24.

3. Yazid b. Mu'awiyah b. Hazn b. Al Muhajjal Yazid is a lesser-known companion of the Prophet. He is reported to have been among the members of the delegation who came to meet the Prophet from Najran. Two inscriptions attributed to him have been found in Najran.

The first reads: May Allah have mercy on Yazid b. Mu'awiyah b. Hazn b. Al Muhajjal. Amin. The second is almost identical, but it adds: "Lord of the Believers, accept him while he lives and the day he dies".

4. Mu'awiyah b. Abi Sufyan Mu'awiyah, one of the Umayyad caliphs, is mentioned in inscriptions on 2 dams which were made during his reign. One of the inscriptions is dated to the year 58 AH.

5. Zayd b. Thabit Zayd was one of the main scribes involved in the collection of the Quran. There is an early inscription mentioning him, which reads: "O Allah forgive Zayd b. Thabit and whoever reads this writing and says Amin. Amin, Lord of the Worlds, Lord of Moses & Aaron."

6. Sa'id b. Al-As Sa'id was also one of the scribes involved in the collection of the Qur'an. A recently discovered inscription, which is partially damaged, seems to read: "I am Sa'id b. al-As. My lord is Allah".

While the inscription is undated, an early date may be supported by the fact that it spells the word allāh with just one lām. This is a pre-Islamic spelling variation that disappears shortly after the rise of Islam.

Adjacent to this is another archaic inscription - written by a person named al-Walid. This inscription could be one of the earliest attestations of the complete shahadah. The author spells the name allāh twice with one lām and once (in the basmala) with two lāms.

7. Alqamah b. Talhah This inscription, which also contains the complete shahadah, was written by a person named Alqamah b. Talhah. As the writing style of this inscription is very old, it's plausible that it was written by a Companion bearing the same name who died in 15 AH.

8. A'ishah The Prophet's wife A'ishah might be mentioned in an inscription dated to 70 AH. This inscription reads: "May Allah and the angels and His pious servants send salutations/blessings upon A'isha. (It was written in) the year 70".

9. Abu Mas'ud This is a fascinating early inscription which states that it was written "at the time Abu Mas'ud was detained/imprisoned". The traditional sources indeed seem to suggest that a Companion bearing the name Abu Mas'ud was detained during the reign of Umar.

While some of these inscriptions challenge revisionist theories and inspire confidence in the Muslim biographical sources, it is important to recognise the limitations of this evidence.

For inscriptions n.o 5-9, more research is necessary to be sure that they are indeed referring to the respective companions. Some of their names were quite common and therefore the possibility that they are referring to other (unknown) early Muslims cannot be excluded.