Benefits of having a Rebbe

 Tanis (23b) R. Mani used often to attend the discourses of R. Isaac b. Eliashab and he complained: The rich members of the family of my father-in-law are annoying me. The latter exclaimed: May they become poor! And they became poor. Later on R. Mani complained: They press me for support and R. Isaac exclaimed: Let them become rich! And they became rich. On another occasion he complained: My wife is no longer acceptable to me. R. Isaac thereupon asked: What is her name? He replied: Hannah. Whereupon R. Isaac exclaimed: May Hannah become beautiful! And she became beautiful. He then complained: She is too domineering over me. Whereupon R. Isaac exclaimed: If that is so, let Hannah revert to her former ugliness! And she became once again ugly.