Is it permissible to deal with a commoner who calls to Allah and from whom knowledge is taken, even if he has sins or bad morals, taking into account the necessity of verifying the authenticity of what he says when in doubt? And what is the criterion for believing a commoner who calls to Allah, trusting what he says, and transmitting knowledge from him?

Every Muslim is obligated to engage in da‘wah (inviting to Islam) and convey what they know of religious matters, and this is not limited to scholars. However, it is forbidden to delve into religious law without knowledge, so whoever possesses knowledge of the Qur’an and Sunnah should invite and teach people. As for one who lacks knowledge, they should not speak about what they do not know, for speaking about Allah without knowledge is worse than shirk (polytheism). Similarly, a Muslim must convey what knowledge they possess to those who do not know it, and it is forbidden for them to say what they do not know. It is necessary to verify what is conveyed by someone not known for their religious knowledge, whereas it is permissible to trust those known for their engagement in it.