Isnad is a term used in Islamic scholarship to refer to the chain of narrators who transmit a particular saying or action of the Prophet Muhammad. It is crucial for verifying the authenticity of hadith, which are the recorded sayings and actions of the Prophet. A strong isnad indicates that the hadith is more likely to be reliable. The process of establishing an isnad involves examining the credibility and memory of each narrator in the chain. Scholars assess the integrity and accuracy of these individuals to ensure that the transmission of knowledge is trustworthy. This rigorous evaluation helps maintain the integrity of Islamic teachings.