Reference for Eruvin 12:15
ואיבעית אימא הא והא לאחר בת קול
<br>(Now is not this<span class="x" onmousemove="('comment',' The Baraitha just cited.');"><sup>37</sup></span> self-contradictory? You said: 'The halachah is always in agreement with Beth Hillel, and then you [proceed to] say: 'But he who wishes to act in agreement with the ruling of Beth Shammai may do so'! - This is no difficulty; the latter statement<span class="x" onmousemove="('comment',' Lit., 'here'.');"><sup>38</sup></span> [was made] before [the issue of] the bath kol<span class="x" onmousemove="('comment',' V. Glos. and cf. infra 13b. The bath kol announced that the halachah was always in agreement with Beth Hillel.');"><sup>39</sup></span> while the former<span class="x" onmousemove="('comment',' Lit., 'here'.');"><sup>38</sup></span> [was made] after [the issue of] the bath kol.<span class="x" onmousemove="('comment',' V. Glos. and cf. infra 13b. The bath kol announced that the halachah was always in agreement with Beth Hillel.');"><sup>39</sup></span> And if you prefer I might reply: Both the former and the latter statements<span class="x" onmousemove="('comment',' Lit., 'that and that'.');"><sup>40</sup></span> [were made] after [the issue of] the bath kol