´It was narrated that Jabir said:` The Messenger of Allah (ﷺ) said: “When anyone of you prostrates let him be balanced in prostration, and not spread his arms as a dog does.”
Hadith Referenceسنن ابن ماجه / كتاب إقامة الصلاة والسنة / 891
1؎: Moderation in prostration (sujud) is that both palms should be placed on the ground, both elbows should be raised off the ground, and the abdomen should be kept separate from the thighs. Hafiz Ibn Hajar said: Spreading the arms on the ground is disliked (makruh) because it is contrary to humility (khushu‘) and proper etiquette. However, if someone remains in prostration for a long time, he may rest his arms on his knees, because in a hadith it is mentioned that a companion complained to the Prophet (sallallahu alayhi wa sallam) about the difficulty of prostration, so he (sallallahu alayhi wa sallam) said: "Seek help from your knees."
Explanation & Benefits
Maulana Ataullah Sajid
Benefits and Issues: ➊ The meaning of moderation in prostration (sujud) is that one should neither remain so high that some parts of the body required for prostration do not touch the ground, nor should one go so low that the entire arms rest on the ground, or the stomach touches the thighs. It can also mean that one should neither prolong the prostration excessively nor make it too brief. However, a very lengthy prostration is prohibited when someone is praying behind you, whether it is an obligatory (fard) prayer or a voluntary (nafl) prayer.
➋ When a dog sits on the ground at ease, it spreads its entire forearms on the ground. It is not correct to spread the arms in this manner during prostration. Rather, the palms should be placed on the ground, and the elbows should remain raised above the ground, as has been mentioned in previous ahadith.
Source: Commentary on Sunan Ibn Mājah by Mawlānā ‘Atā’ullāh Sājid, Page: 891
´Jabir narrated that :` the Prophet said: "When one of you prostrates, then let him be balanced, and let him not lay his forearms down like the lying of the dog."
Shaykh Dr. Abdur Rahman Freywai
1: That is, maintain a moderate posture such that the abdomen remains level, both elbows are raised from the ground, and the sides are separated from the body, and the abdomen is also separated from the thighs. It should appear as if there is a gap between the ground and the upper half of the body.
2: By "like a dog" is meant that it sits by spreading both its elbows on the ground; do not perform prostration (sujud) in this manner.
Source: Sunan al-Tirmidhi – Majlis ‘Ilmi Dar al-Da‘wah, New Delhi Edition, Page: 275