During the nesius of the Mitteler Rebbe, when questions in halacha were sent to him, he would give them to the Tzemach Tzedek to answer. The Tzemach Tzedek would write a Teshuva, and then bring it to the Mitteler Rebbe for approval. After the Mitteler Rebbe gave his approval, the teshuva would then be sent out. However, the Mitteler Rebbe never took issue with any of the teshuvos of the Tzemach Tzedek.

Once, an urgent query arrived, and the Mitteler Rebbe was not available. The Tzemach Tzedek decided that, in light of the fact that the Mitteler Rebbe always approved of his Teshuvos, and being that an immediate response was required, he would send out the Teshuva this once before showing it to the Mitteler Rebbe. When he later told the MR about, he asked the Tzemach Tzedek what he had answered in the Teshuva, and then showed him that it was contrary to an explicit tosefos.

The Tzemach Tzedek was very upset about this, so the Mitteler Rebbe said to him: “Don’t feel bad, in the meantime you are not a Rebbe!”

Even the Torah learning of the Tzemach Tzedek, with all of his phenomenal genius, had to be connected to the Mitteler Rebbe, who was then the Rebbe.