1. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad ibn ‘Isa from Hammad ibn ‘Isa from Hariz from Zurarah and Ali ibn Ibrahim has narrated from his father from Hammad from Hariz from Zurarah who has said the following: “Abu Ja’far (a.s.), has said, ‘When you want to kneel for Ruku‘ say, ‘Allah is great’ before it, then assume Ruku‘ position and say, ‘O Lord, I have knelt down for You, I am submitted to You, I believe in You, and I plead before You to be my attorney. You are my Lord. My heart, my ears, my eyes, my hairs, my skin, my flesh, my blood, my bone marrow, my bones, my nerves and all that my legs support of me are humble before You without reservations, arrogance or tiredness.’ Say three times, ‘My Lord, the great, is free of all defects and I praise Him,’ with clarity and fluency. In Ruku‘ position you should level up your feet with a distance of one shibr (eight inches) between them, place your palms over your knees, first your right palm on the right knee, and then the left palm over your left knee. Open your fingers and make them to hold the sides of your knees, keep your back straight, stretch your neck forward and keep your eyes to look between your feet. Then, while standing straight, say, ‘Allah hears all who praise Him. All praise belongs to Allah, Lord of the worlds, the owner of might and majesty. Greatness belongs to Allah, Lord of the worlds,’ raise your voice when saying this, then raise your hands for saying ‘Allah is great’ and then bow down for sajdah.”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

2. Muhammad ibn ’Isma‘il has narrated from al-Fadl ibn Shadhan from Ibn Abi ‘Umayr from Jamil ibn Darraj who has said the following: “I once asked abu ‘Abd Allah (a.s.), about what one says when performing behind an Imam when he says, ‘Allah hears all those who praise him.’ He (the Imam) said that he must say, ‘All praise belong to Allah, Cherisher of the worlds’ and lowers his voice.’”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

3. Ali ibn Ibrahim has narrated from his father from Hammad ibn ‘Isa from Hariz from Zurarah who has said the following: “Abu Ja‘far, ‘Alayhi al-Salam, has said, ‘When you decide to assume Ruku‘ (bowing down on one’s knees) and Sajdah (prostration) position, raise your hands, say Takbir (Allah is great beyond description), then assume Ruku‘ (bowing down on one’s knees) and Sajdah (prostration) position.’”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

4. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from al-Husayn ibn Sa‘id from Fadalah ibn Ayyub from abu al- Mighra’ from abu Basir who has said the following: “Abu ‘Abd Allah (a.s.), has said that ’Amir al-Mu’minin has said, ‘One who does not straighten his back during Salah (prayer), his Salah (prayer) is not valid.’”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

5. Al-Husayn ibn Muhammad has narrated from ‘Abd Allah ibn ‘Amir from Ali ibn Mahziyar from Muhammad ibn ’Isma‘il ibn Bazi‘ who has said the following: “I saw abu al-Hassan (a.s.), perform Ruku‘ (bowing down on one’s knees) and make it lower than all of those whom I have seen performing Ruku‘. He spread, in the position of Ruku‘ his arms like wings.’”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

6. Ahmad ibn Idris has narrated from Ahmad ibn Muhammad from al-Husayn ibn Sa‘id from al-Qasim ibn Muhammad from a man from abu Basir from who has said the following: “Abu ’Abd Allah (a.s.), has said, ‘When you stand up straight after Ruku‘ (bowing down on one’s knees), make your back (bones) stand straight (vertically), otherwise, one’s Salah (prayer) is not considered Salah (prayer).”’

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

7. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from al-Sindiy ibn al-Rabi’ from Sa‘id ibn Janah who has said the following: “I once was in the presence of abu Ja‘far (a.s.), in his home in al-Madinah. He initiating a conversation saying, ‘One who completes his Ruku‘ (bowing down on one’s knees) does not face any dread in the grave.’”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

8. Muhammad ibn Yahya has narrated from Muhammad ibn al-Husayn from Ja‘far ibn Bashir form Hammad from Hisham who has said the following: “I once asked abu ‘Abd Allah (a.s.), ‘Is it sufficient for me to say Tahlil, (no one deserves worship except Allah) and Takbir (Allah is great beyond description) in Ruku‘ (bowing down on one’s knees) instead of Tasbih (Allah is free of all defects). He (the Imam) said, ‘Yes, it is sufficient.’”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

9. Ahmad ibn Idris has narrated from Muhammad ibn Ahmad from Ya’qub ibn Yazid from Ibn Abi ‘Umayr from Ali ibn ‘Uqbah who has said the following: “Once abu al-Hassan (a.s.), saw me, in al-Madinah when I performed Salah (prayer). I bent down my head and stretched in my Ruku‘ (bowing down on one’s knees). He (the Imam) sent me a message that said, ‘You must not do so (when you are in Ruku‘).’” (Ahadith 2-9 are best explained in the form of fatwa.)

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.