In the book “The Creed of the Distinguished Imam Ahmad ibn Hambal”, Abul-Fadl At-Tamimiyy Al-Baghdadiyy, the head of the Hambaliyy scholars in Baghdad [1], the son of the head of the Hambaliyy scholars in Baghdad, said [Page 45]:
وَأَنْكَرَ أَحْمَدُ عَلَى مَنْ يَقُولُ بالجِسْمِ (أَي فِي حَقِّ اللَّه) وَقَالَ إِنَّ الأَسْمَاءَ مَأْخُوذَةٌ مِنَ الشَّرِيْعَةِ وَاللُّغَةِ وَأَهْلُ اللُّغَةِ وَضَعُوا هَذَا الاسْمَ عَلَى ذِي طُوْلٍ وَعَرْضٍ وَسُمْكٍ وَتَرْكِيْبٍ وَصُوْرَةٍ وَتَأْلِيْف وَاللَّهُ تَعَالَى خَارِجٌ عَنْ ذَلِكَ كُلِّهِ (أي منزه عنه) فَلَمْ يَجُزْ أَنْ يُسَمَّى جِسْمًا لِخُرُوجِهِ عَنْ مَعْنَى الجِسْمِيَّةِ وَلَمْ يَجِئْ فِي الشَّرِيعَةِ ذَلِكَ فَبَطَلَ اهـ
which means “Al-Imam Ahmad objected to whoever says Allah is a jism (body), and said: “Indeed, the names (of things) are taken from the Religion and the language. (As for the language,) the linguists applied this word jism for that which has length, width, depth, a construction, an image/appearance, and an (ordered/arranged) composition. And Allah the Exalted is clear of all of that. So, it is not permissible to say about Allah that he is a jism because He is clear of corporeality (being a body). And it did not come in the Religion, and so it is invalid (to call Allah a body).”
Al-Bayhaqiyy also mentions this about Al-Imam Ahmad in his book Manaqib Ahmad.
Al-Imam `Ahmad ibn Hambal said:
«مَنْ قَالَ اللَّهُ جِسْمٌ لَا كَالأَجْسَامِ كَفَرَ»
which means “Whoever says: Allah is a body not like other bodies blasphemed”. Mentioned by Al-Hafidh Badruddin Az-Zarkashiyy [B:745 D:791]in his book Tashnif Al-Masami^ [Volume 4, Page 648].
[1] a Hambaliyy pundit approved even by Ibn Taymiyah