This cave is the traditional abode of Saint Matthew.
Thence we ascended to the traditional abode of Mar Mattai, the founder, consisting of two narrow grots, not far from the summit of the mountain, in one of which is a small altar hewn out of the rock, and in the other an oblong niche, evidently intended for a bed. Here our guide pointed out to us two holes in the ground, which are said to have been worn by the knees of the hermit. There is a Syriac inscription over the altar, but so defaced, that we could not decipher it. Badger 1852, p 98
Badger, George Percy. 1852. The Nestorians and their Rituals. Google Books