What is the ruling on strengthening hadiths by gathering their chains of transmission?

The Shaykh : There is a detail in this matter that must be addressed. Then, one should seek assistance in mastering this science through books of takhrij (tracing a hadith to its sources), for there one will find new knowledge that is not found in books of terminology or books of biographies. This is the science of takhrij, because there you will find the application of a rule from the rules of terminology. For example, strengthening a hadith by the multiplicity of its chains, and not strengthening a hadith by the multiplicity of its chains. This is a thorny and precise issue, and therefore some of our young brothers get entangled in it; at times they strengthen a hadith merely because its chains are present, or they weaken a hadith on the claim that all the individual chains of this hadith are weak, because they did not understand that rule in a practical and correct way. Likewise, in books of takhrij, the difference will become clear to them between what they read in the science of terminology regarding the definition of an anomalous narration (shadhdh), and what they also read about the acceptance of an addition by a trustworthy narrator. Often, this matter becomes confused for some of the youth: how is an addition by a trustworthy narrator acceptable, and how is a hadith of a trustworthy narrator rejected because it contradicts one who is more trustworthy than him? How does this meet with their statement that an addition by a trustworthy narrator is acceptable? All these matters cannot be known by a student of knowledge merely because he read the terminology or read something from the books of men (narrators). He should proceed to apply what he has read, and books of takhrij for certain works will assist him in this, such as the takhrij of al-Ihya by al-Hafiz al-'Iraqi, the takhrij of al-Hidayah by al-Hafiz al-Zayla'i, and the takhrij of Ibn 'Asqalani known as al-Talkhis al-Habir fi Takhrij Ahadith al-Rafi'i al-Kabir. In reality, books of takhrij are numerous, some concise and some simplified. If a student of knowledge proceeds in these three areas, he can, with time, become independent in judging a hadith with what it deserves of validity or weakness, while considering all these aspects so that he does not fall into error as has happened today.