Reference: Siyar A’laam an-Nubalaa – Volume 8, Page 297
Qays ibn ‘Alee said:
I saw Yazeed ibn Zuray’ in a dream; So I said to him what did Allaah do with you? He replied: He entered me into Paradise. I said to him: With what (meaning, what did you do to earn that)? He said: For [exerting myself in] much prayer.