Responsa for Rosh Hashanah 64:26
לא עולין באילן ולא רוכבין על גבי בהמה כו': השתא דרבנן אמרת לא דאורייתא מיבעיא זו ואין צריך לומר זו קתני:
EITHER WITH AN IMPLEMENT THE USE OF WHICH IS FORBIDDEN ON ACCOUNT OF SHEBUTH<span class="x" onmousemove="('comment',' I.e., merely to make a distinction between Sabbath (or holydays) and weekdays, and not because any 'work' in the strict legal sense is involved. For shebuth, v. Glos.');"><sup>45</sup></span> OR WITH ONE THE USE OF WHICH IS FORBIDDEN BY EXPRESS PROHIBITION.<span class="x" onmousemove="('comment',' Found in or based on the Pentateuch.');"><sup>46</sup></span> IF ONE, HOWEVER, DESIRES TO POUR WINE OR WATER INTO IT HE MAY DO SO.<span class="x" onmousemove="('comment',' And we do not say that he is carrying out repairs, which is forbidden on the Sabbath or holydays.');"><sup>47</sup></span> CHILDREN NEED NOT BE STOPPED FROM BLOWING; ON THE CONTRARY, THEY MAY BE HELPED<span class="x" onmousemove="('comment',' Lit., 'we occupy ourselves with them'.');"><sup>48</sup></span> TILL THEY LEARN HOW TO BLOW. ONE WHO BLOWS MERELY TO PRACTISE<span class="x" onmousemove="('comment',' Lit., 'one who occupies himself'.');"><sup>49</sup></span> DOES NOT THEREBY FULFIL HIS RELIGIOUS OBLIGATION, NOR DOES ONE WHO HEARS THE BLAST MADE BY ANOTHER WHEN PRACTISING. <big><b>GEMARA: </b></big>What is the reason [why these things may not be done]? - The blowing of the shofar is [based on] a positive precept,<span class="x" onmousemove="('comment',' Num. XXIX, 1. It shall be a day of blowing the horn unto you.');"><sup>50</sup></span> whereas the observance of the holyday is [based both on] a positive<span class="x" onmousemove="('comment',' Lev. XXIII, 24: In the seventh month . . shall be a solemn rest unto you.');"><sup>51</sup></span> and a negative precept,<span class="x" onmousemove="('comment',' Ibid. 25: Ye shall do no manner of servile work.');"><sup>52</sup></span> and a positive precept cannot override both a positive and a negative precept. NOR TO CLIMB A TREE NOR TO RIDE ON AN ANIMAL etc, Seeing that you have not allowed even Rabbinical [prohibitions to be broken],<span class="x" onmousemove="('comment',' The prohibitions to exceed the Sabbath limit and to remove debris are purely Rabbinical, without basis in the Pentateuch. (Rashi) .');"><sup>53</sup></span> need you mention Pentateuchal ones?<span class="x" onmousemove="('comment',' Riding and climbing are forbidden because they might lead to the cutting or plucking of a branch, which is forbidden by the Pentateuch. The argument is very forced, and Rashi is inclined to regard the whole sentence as spurious. [R. Hananel takes the prohibitions regarding the Sabbath limit and removing the debris to be the Biblical prohibitions referred to.]');"><sup>54</sup></span> - The Mishnah adopts the style of 'A, and needless to say B'.