Musar for Eruvin 195:7

חוץ לארבע אמות דאי מייתי ליה אתי לידי חיוב חטאת לא שרו ליה רבנן

but where it rested without the four cubits in which case, if he had brought it back,<span class="x" onmousemove="('comment',' Where the whole of [he scroll had fallen down and he carried it along a distance of more than four cubits in a public domain.');">¹⁶</span> he would have incurred the obligation of a sin-offering, the Rabbis did not permit it to him.<span class="x" onmousemove="('comment',' Even where one end remained in his hand and only a shebuth is involved. To safeguard a Pentateuchal prohibition a shebuth was justifiably instituted.');">¹⁷</span> But if so,<span class="x" onmousemove="('comment',' That according to R. Judah a preventive measure was enacted, even in the case of holy writings, against the possibility of the infringement of a Pentateuchal law.');">¹⁸</span>

Mesilat Yesharim