Midrash su Deuteronomio 1:46

(Fol. 21) MISHNAH: Whoever reads the Megilla standing or sitting has fulfilled his duty. GEMARA: We are taught in a Baraitha: "It is not so with the reading of the Torah, [which can be read only while the reader is] standing. Whence do we infer this? R. Abahu said: "The passage says (Deut. 5, 28) But as for thee, stand thou here by me. From this we infer that the reader should stand, and the congregation sit." R. Abahu said again: "Whence do we know that the master should not teach the disciple when he sits on the bed, and the disciple on the floor? Because it is written But as for thee, stand thou here by me. (Just as I stand so you should stand. ) " Our Rabbis were taught: From the time of Joshua till Rabban Gamaliel the Torah was studied standing. When Rabban Gamaliel the elder died, sickness became prevalent, and they began to study sitting. And this is the meaning of the Mishnah: "Since Rabban Gamaliel the elder died the dignity of the Torah has ceased." One passage says (Deut. 9, 9) I sat on the mount forty days and forty nights; and another (Ib. 10, 10) I stood on the mount. Said Rab: "He stood when he studied, and he sat when he repeated." R. Chaninah said: "He was neither standing nor sitting, but bending." R. Abba, however, said: "Sitting means nothing else but abiding, as it is said (Deut. 1, 46) Ye sat in Kadesh [which means dwelt]." Raba said: "The easy things he studied while standing, and the difficult things while sitting."