Abu Dawud

756. Commentary:
This hadith is weak.

➊ Allamah Shawkani rahimahullah has written that in its chain of narration is Abdur Rahman bin Ishaq al-Kufi, and Imam Ahmad bin Hanbal rahimahullah considers him weak.

➋ Imam al-Bukhari rahimahullah says, “There is some criticism regarding him.” (i.e., he is a weak narrator.)

➌ Imam Nawawi rahimahullah has written: “This narration is unanimously weak.” And in the narration that follows, it is also reported from Ali radi Allahu anhu that he placed his hands above the navel.

In the authoritative Hanafi fiqh book "al-Hidayah" it is stated:
«قال: ويعتمد بيده اليمنى على اليسرى تحت السرة، لقوله - عَلَيْهِ الصَّلَاةُ وَالسَّلَامُ -: إن من السنة وضع اليمين على الشمال تحت السرة»
“That it is narrated from Ali (radi Allahu anhu) that placing the right hand over the left and placing them below the navel is Sunnah.”

But in its commentary, "al-Binayah Sharh al-Hidayah," Allamah ‘Ayni Hanafi rahimahullah writes:
«من حديث عبد الرحمن بن إسحاق الواسطي عن زيادة بن زيد السوائي عن أبى جحيفة عن على - رَضِيَ اللَّهُ عَنْهُ - أنه قال: السنة وضع الكف على الكف تحت السرة، وقال أحمد وأبو حاتم: عبد الرحمن بن الحارث أبو شيبة الواسطي، منكر الحديث. وقال ابن معين: ليس بشيء، وقال البخاري: فيه نظر، وزيادة بن زيد لا يعرف، وقال النووي فى الخلاصة فى " شرح مسلم ": هو حديث ضعيف متفق على ضعفه،»
“That this narration has been transmitted by ‘Abd al-Rahman ibn Ishaq al-Wasiti.
And Imam Ahmad and Imam Abu Hatim have called this narrator ‘munkar al-hadith’ (one whose narrations are rejected).
And Imam Ibn Ma‘in says: ‘He is nothing (i.e., not reliable).’
Bukhari says: ‘There is criticism regarding him.’
And Allamah Nawawi says: ‘This hadith is, by consensus, weak.’
....................
Allamah ‘Ayni further writes:
«فإن قلت: كيف يكون الحديث حجة على الشافعي وهو حديث ضعيف لا يقاوم الحديث الصحيح والآثار التى احتج بها مالك والشافعي، هو حديث وائل بن حجر أخرجه ابن خزيمة فى " صحيحه " قال: صليت مع رسول الله - صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ - فوضع يده اليمنى على اليسرى على صدره»
‘How can the hadith of Ali (radi Allahu anhu) regarding placing the hands below the navel be used as evidence against Imam Malik and Imam Shafi‘i, when it is an extremely weak narration?
And it cannot stand against the authentic hadith and reports which are the evidence of Imam Malik and Imam Shafi‘i. Their evidence is the narration of Sayyiduna Wa’il (radi Allahu anhu) in Sahih Ibn Khuzaymah,
He says: I performed prayer behind the Prophet (sallallahu alayhi wa sallam), and he (sallallahu alayhi wa sallam) placed his right hand over his left hand and bound them upon his chest.’”