How can a hadith be authentic?

Question : The questioner asks: How can it be that all the men in a hadith are trustworthy, yet the hadith is weak in its chain of narration?

Answer : Yes, that is not correct. It is not correct for all the men to be trustworthy and for the hadith to be weak in its chain of narration. However, with regard to the chain, it may be weak even if all the men are trustworthy, if the hadith is suspended, or missing the Companion link, or has a broken chain. It is also possible that all the narrators are trustworthy, but the text of the hadith is weak, such that it is anomalous or has a defect that invalidates it.
The important point is that a student of hadith should know that the authenticity of a hadith is not limited to the trustworthiness of the men. Rather, there are five conditions for a hadith to be authentic: the chain must be connected, the narrator must be upright, yes, he must be precise, and the text must not have a defect or be anomalous. These are the five conditions. Here, we must be aware that some people who publish hadiths rely heavily on the apparent chain of narration. They authenticate a hadith without looking at its defects. A hadith that appears authentic in its chain may actually have a defect that requires it to be rejected. The defects of hadiths are numerous, and the science of defects is one of the most precise and deepest sciences of hadith. For this reason, it is not grasped except by the most expert of hadith scholars, as al-Hafiz Ibn Hajar said in his commentary on al-Nukhba. Therefore, the brothers who are concerned with hadiths and tracing them to their sources should pay attention to this issue, because we have seen errors in this matter from great scholars in our time. They look at the apparent chain and then rule that the hadith is authentic based on the appearance of this chain, regardless of the text of the hadith. This is a flaw.