Pesachim 10th perek.
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From the preceding Boraitha we may infer eight things: First: One who included the Habdalah in his evening prayer must nevertheless recite it again over a cup (this is inferred from the sentence “if a man enter his house at the close of the Sabbath,” which signifies, that he came from the house of worship, where he had already recited the Habdalah). Second: The benediction after a meal must be made over a cup (of wine). Third: The cup used at the benediction must be of a prescribed capacity (i.e., a quarter of a lug; for were this not so, it could be divided and part used for the Habdalah and another part for the other benediction). Fourth: One who pronounces the benediction over the cup of wine must taste some (for otherwise the benediction could be made and the wine left over for the next benediction). Fifth: As soon as part of the wine is tasted after a benediction, the cup of wine is rendered unfit for any other benedictions. Sixth: Even if a full meal is eaten at the close of Sabbath and the sanctification of the day had passed, it is still a duty to recite the Habdalah. Seventh: Two degrees of sanctification may be bestowed upon one cup of wine. Lastly: The entire Boraitha is in accordance with the school of Shammai and with the interpretation of R. Jehudah (i.e., that the benedictions over light must be pronounced prior to that over spices, and not vice versa)