(a) It is reported from Sayyiduna Ali (may Allah be pleased with him) that he went out and saw some people praying with their garments hanging down, and he (may Allah be pleased with him) said: "It is as though they are Jews who have come out of their 'fihr'."
(b) Abu Ubayd (may Allah have mercy on him) says: "Fihr" is their place of worship, or a place where they gather. And "sadl" means that a man lets his garment hang down in front without bringing its two edges together. If he brings the edges together, it is not "sadl".
(c) In one of the two narrations reported from Sayyiduna Ibn Umar (may Allah be pleased with them both), he declared it disliked (makruh). Likewise, Mujahid (may Allah have mercy on him) and Ibrahim al-Nakha'i (may Allah have mercy on him) also called it disliked, and it is reported from Jabir (may Allah be pleased with him), al-Hasan (may Allah have mercy on him) and Ibn Sirin (may Allah have mercy on him) that there is no harm in it.
(d) The concession they gave in this is for one who does not do it out of arrogance; but one who does it out of arrogance is forbidden from it. Imam al-Shafi'i (may Allah have mercy on him) pointed to this same meaning in the book of al-Buwayti.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 3313