—by authenticating such a report as this one (1) and others even more aberrant and objectionable (2). His readiness to pronounce defective traditions sound and to deny that they suffer from hidden flaws is exactly like his rejection of meanings, causal links, and analogical reasoning in which both the original case and the branch are identical in every respect. The man authenticates reports that the whole body of hadith scholars unanimously consider weak, and this is evident to anyone who examines his writings.
As for your claim that “Imam Ahmad narrated it, built his legal opinion upon it, voiced no criticism of it, and that whatever he leaves unchallenged in the Musnad is therefore authentic in his view,”
these are four separate premises. Even if we were to grant you all four, the most that could be inferred is that Ahmad deemed the report sound. Yet the scholars whose statements we have already cited disagreed with him, declaring the hadith weak, labeling it aberrant, and testifying that it is not from the words of the Messenger of Allah ﷺ.
When Ahmad and other hadith masters differ over a report, the decisive arbiter between them is the evidence itself; his opinion is no proof against theirs—just as, were he to differ with another jurist on a point of law, his view would not oblige his opponent. The final, conclusive proof is the evidence.
Had we argued in the same way against you, you would—quite rightly, and we would have heard your protest—have said: “Ahmad’s authentication is countered by these scholars’ verdict of weakness, and so it cannot serve as proof.”