It is narrated from Sayyiduna Umayr (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) addressed them and said: "May Allah Almighty keep radiant the person who heard a saying from us and preserved it (in memory), for many a carrier of fiqh (knowledge of the religion) is not himself a person of understanding, and many a carrier of fiqh conveys it to someone who has more understanding than he."
This hadith is not narrated from Sayyiduna Umayr bin Qatadah al-Laythi (may Allah be pleased with him) except with this chain, and Hisham bin Ammar (may Allah have mercy on him) is alone in narrating it.
Hadith Referenceالمعجم الأوسط / باب الميم / 7004
Hadith Takhrij«أخرجه الطبراني فى «الكبير» برقم: 106»