Reference for Chullin 214:19

ור' יוחנן אמר

The waiter must say a Benediction for each cup [of wine that he receives], but does not say a Benediction for each piece [of bread].<span class="x" onmousemove="('comment',' The waiter can expect to receive from the diners a morsel of bread from time to time, therefore the benediction for the first piece would serve also for the subsequent pieces. He cannot however be certain that he will receive wine from time to time, therefore each time he must make a benediction.');">⁸</span>

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