Reference for Berakhot 1:3
בֵּית שַׁמַּאי אוֹמְרִים, בָּעֶרֶב כָּל אָדָם יַטּוּ וְיִקְרְאוּ, וּבַבֹּקֶר יַעַמְדוּ, שֶׁנֶּאֱמַר (דברים ו) וּבְשָׁכְבְּךָ וּבְקוּמֶךָ. וּבֵית הִלֵּל אוֹמְרִים, כָּל אָדָם קוֹרֵא כְדַרְכּוֹ, שֶׁנֶּאֱמַר (שם) וּבְלֶכְתְּךָ בַדֶּרֶךְ. אִם כֵּן, לָמָּה נֶאֱמַר וּבְשָׁכְבְּךָ וּבְקוּמֶךָ, בְּשָׁעָה שֶׁבְּנֵי אָדָם שׁוֹכְבִים, וּבְשָׁעָה שֶׁבְּנֵי אָדָם עוֹמְדִים. אָמַר רַבִּי טַרְפוֹן, אֲנִי הָיִיתִי בָא בַדֶּרֶךְ, וְהִטֵּתִי לִקְרוֹת, כְּדִבְרֵי בֵית שַׁמַּאי, וְסִכַּנְתִּי בְעַצְמִי מִפְּנֵי הַלִּסְטִים. אָמְרוּ לוֹ, כְּדַי הָיִיתָ לָחוּב בְּעַצְמְךָ, שֶׁעָבַרְתָּ עַל דִּבְרֵי בֵית הִלֵּל:
Beth Shammai say: In the evening all men recline [on their sides, it being written: "when you lie down" — in the manner of lying down] and in the morning they stand, [it being written: "and when you arise" — in the manner of rising], as it is written (Deuteronomy 6:7): "and when you lie down and when you arise." And Beth Hillel say: Each man recites it in his own way, [either standing, sitting, reclining, or walking] it being written (Ibid.): "and in your walking on the way." If so, why is it written "when you lie down and when you arise"? The time when men lie down, and the time when men arise. R. Tarfon said: "Once, while on the road, I reclined to recite it in accordance with Beth Shammai, and I came close to being set upon by robbers" — whereupon they said to him: "You would have deserved to be killed [(and if you had died, your blood would have been upon your own head)] for having transgressed the words of Beth Hillel."