Imaam Maalik bin Anas 179 AH said,

ان هذا العلم هو لحمك و دمك و عنه تسأل يوم القيامة فانظر عمن تأخذه

“Indeed this knowledge is your flesh and blood, and on the Day of Judgement you’ll be asked about it. Therefore, look to whom you take (knowledge) from.”

Source: al-Kifaayah 21