Muftī Ismail Moosa (may Allāh Ta’ālā preserve him)
Many students and even some scholars latch onto the concept of Jarh (criticizing narrators of Aḥādīth) and use that as proof to condemn any scholar who disagrees with them. Little do they realize that there are stringent conditions and rigorous principles that apply.
Besides the essential and integral condition of a person being an expert and Imām before he can speak against another, the principles of Tajrīḥ al-Muqārin (speaking ill of a contemporary), Jarḥ al-Mubham (not presenting a valid reason for the criticism), Condemning with an ulterior motive, etc invalidates lots of condemnations spewed out by students and new graduates of today.
The stringent conditions and principles also applies to the comments of senior scholars, as it always was applicable to the greatest of Muḥaddithīn. The statements of great Imāms and experts of Khayr al-Qurūn were evaluated according to these principles. Thus, all the more reason the statements of the leading scholars of today will also be bound by these principles.
Even if great scholars or pious people have to speak ill of another scholar of today, then too, the students and disciples should not just accept it.
Technically, if the greatest saint of today, the most pious person of this era, the absolute knowledgeable person of this age, the teacher who you hold in the most esteem, or the Shaykh who you have the most regard for, has to speak against another scholar who is alive, his remarks has to be properly analyzed and will have to go through a thorough scrutiny.
Since this pious saint, or this knowledgeable scholar, or this respected teacher, or Shaykh of yours is speaking against a contemporary, one will have to explore the reasons and motives of his statements. A younger scholar cannot just accept from a senior scholar on the basis that the scholar is his Ustāḍ or Shaykh. Rather, there are so many laws and factors for him to consider.
If that is the conditions when our elders speak against a present day scholar, then how much more caution we need to exercise before we can blurt out a criticism against those who probably serving the Dīn and helping other Muslims, and humanity at large, more than us.
We ask Allāh Ta’ālā to protect us to destroying the Dīn under the assumption that we are serving this beautiful religion.