This research studies the inscription of Abdullah bin Yazid Al-Saluli, which was found in 2002 by the joint Saudi-Japanese mission in Wadi Al-Khushaybah in Hima region-Najran. The importance of this inscription derived from it is being one of the oldest Islamic inscriptions, as it is dated back to the year of 29 AH (as will be explained in the research) which makes it comes in the third rank in terms of dated Islamic inscriptions, after Salamah inscription dated 23 AH and Zuhair two inscriptions dated 24 AH.

This inscription can be classified within the commemorative Islamic writings that executed on the rocks of the roads' paths for proving presence in the place and an expression of faith and piety. It is a written document that has an important historical and cultural significance with the religious and social contents and names it contains. It is also an authentic witness of its era culture that dated back, as well as its importance in studying the development of Arabic calligraphy in that early history of Islamic period.

The Saudi-Japanese team referred to this inscription in their preliminary report An annually report

This inscription was referred to in a preliminary report on the work results done by the Saudi-Japanese team in Najran and Medina regions, published in Atlal Annual book (Issue 18 - 1426 AH / 2005), and it was also referred to in a general study on the rock inscriptions and drawings in Wadi Al-Khushaybah in Najran, published by Kawatoko and et al, issued by the Middle East Culture Center in Japan and the University of Tokyo (2005 AD).

The inscription did not receive a detailed comparative study covering its content and historical connotations, which will be handled by the researcher in this research.