A similar hadith is narrated from Sayyiduna Bara’ bin ‘Azib (may Allah be pleased with him), except that in one of his narrations the words are ‘ala al-sufuuf al-awwal (upon the first rows) and in another narration the words are ‘ala al-saff al-muqaddam (upon the front row).
Hadith Referenceالفتح الربانی / أبواب صلاة الجماعة / 2659