Abu Huraira said, "I have kept in my memory two large quantities*
of learning from God’s messenger, one of which I have disclosed among
you; but were I to disclose the other, this bul'um, meaning the food
tract, would be cut". Bukhari transmitted it.
*Lit. receptacles, or vessels.
Narrated Al-Hasan said that knowledge is of two kinds:
knowledge in the
heart, which is the beneficial type; and knowledge on the tongue, which
is God’s allegation against a human being.” Darimi transmitted it.
If any of you people knows anything he should
make it known, but if anyone does not know he should say that God
knows best, for saying this when one does not know is a part of knowledge. God said to His prophet, “Say, I do not ask you for any reward
for it, and I am not a pretender.”* (Bukhari and Muslim.)
*Qur’an, xxxviii, 86.
Ziyad b. Hudair said that ‘Umar asked him whether he knew what
demolishes Islam, and that when he replied that he did not, he said,
"The slip of a learned man, the disputation of a hypocrite about the
Book, and the rule of imams who lead men astray.” Darimi transmitted
it.