Imam Kazim (as) debate with Abu Yusuf

Harun al-Rashid ordered Abu Yousif to ask Imam Musa in his presence, that incapability might appear on him and he would use it as a means to degrade his dignity. When the Imam, peace be on him, met them, Abu Yousif asked him:
- What do you say about making shade (from the sun) for the person consecrated as (muhrim)?
- It is not permitted.
- Shall he pitch a tent and enter it?
- Yes.
- What is the difference between the two places?
- What do you say about a menstruating woman-does she compensate the prayer?
- No.
- Does she compensate the fasting?
- Yes.
- Why?
- In this manner it has been mentioned, and in this manner this has been mentioned.
Abu Yousif kept silent and gave no answer. Shame and incapability appeared on his face, so Harun said to him:
- I think you have done nothing!
- He has given me an irrefutable answer!
Imam Musa left them and went away while sadness and unhappiness dominated them. ( Al-Manaqib, vol. 3, p. 429.)