"But behold, they are upon the surface of the earth," meaning: upon the earth, having emerged from its interior.
Muhammad said: Al-Sahirah (the surface) according to the scholars of the language is the face of the earth, and this is the meaning of the statement of Yahya.
Tafsir of Surah al-Nazi'at from verse (15-26)
﴿فَإِذا هم بالساهرة﴾ أَيْ: بِالْأَرْضِ قَدْ خَرَجُوا مِنْ بَطْنِهَا.
قَالَ مُحَمَّدٌ: السَّاهِرَةُ عِنْدَ أَهْلِ اللُّغَةِ: وَجْهُ الْأَرْضِ، وَهُوَ معنى قَول يحيى.
تَفْسِير سُورَة النازعات من آيَة (١٥ - ٢٦)