by Rabbi Berach Steinfeld
The Torah in Bereishis 1:31 says that it was evening and then it was morning, the sixth day. This is the only day where the Torah adds the prefix heh to the number of the day.
The Medrash Rabba 9 quotes Rav Yudin saying the heh is referring to the extra time we add onto Shabbos and we are “mosif meichol al hakodesh.” Since this was the time in which the world was finished, the Torah therefore adds the letter heh. We could kler regarding the addition from chol onto kodesh where one cannot do melacha; does it mean the part added is like a part of the day of Shabbos and it is considered Shabbos and not Friday, just a little bit lenient in the fact that there is no chiyuv asseh not to work during that time? Or is it considered a day of chol, it is just a separate mitzvah to be mosif to the kodesh during a time of chol, hence it would be considered Friday and not Shabbos. In addition, even if we say that the din of Shabbos is chal on the added time of Friday, does that mean that the time itself that was added has kedushas Shabbos or that one has a chiyuv to add part of one’s Friday to make it holy? From the above Medrash it would seem that it is considered Friday, hence the letter heh before shishi and it would seem that there is a chiyuv to sanctify part of Friday to keep it holy.
The Trumas Hadeshen 80 writes that one does not say tachanun at Shacharis when a Chosson davens in Shul on the day of his wedding because he considers the entire day a day of simcha. This is similar to Erev Pesach when one does not say Lamnatzeach because the korban Pesach was brought on that day and we know that the Pesach could only be brought in the afternoon. The Pri Megadim in Orach Chaim 131:10 asks why do we say tachanun on Friday where part of the day has kedushas Shabbos? He answers that the addition to Friday is a result of the night of Shabbos which is really the next day, whereas Pesach is part of the day albeit the korban may only be brought in the afternoon. It is still the same day. From this Pri Megadim we see that the tosefes Shabbos is a chelek of Friday, not Shabbos; otherwise there would be no question. According to the tirutz of the Pri Megadim we see the opposite and since the tosefes is connected to the night, it is not part of Friday, but rather Shabbos. We could argue and say that even according to the tirutz of the Pri Megadim the tosefes Shabbos is still a part of Friday, but since it connects to the next day (meaning that night) it is different than Erev Pesach, which is actually that same day.
The above question can be used to explain the machlokes of the Taz and the Maharshal. The Taz in Orach Chaim 291:6 quotes the Maharshal who was makpid not to eat the seuda Friday night until it was vadai layla. The Taz said that since tosefes Shabbos is DeOraysa one may eat and finish the meal while it has yet to turn dark. This would depend on the fact whether or not tosefes Shabbos makes it Shabbos, or is it really Friday with restrictions of Shabbos.
The Taz in 568:1 quotes the Maharshal in the name of Rav Tevil that he would not start the meal on Shmini Atzeres until it was vadai layla because it would put him in the predicament that he might have to make a “leisheiv basuccah” since it was still during the day-time hour which would bring a tarti desasri of saying leisheiv which indicates Hoshana Rabba and making Kiddush and saying Shmini Atzeres in Kiddush. The Maharshal says that you can’t say the fact that he was mosif meichol al hakodesh makes it as if Hoshana Rabba ended and Shmini Atzeres began. He says it is true one can daven early on Shmini Atzeres and mention Yom Tov in his tefillah, but it is still not considered night as the same would apply to davening early on Friday night. The proof for this is that one would have to say Krias Shema later at night. The Taz would go according to his shita that one could be mekabel Shabbos early, thereby making it already Shabbos.
Halacha lemaaseh should be consulted with your Rov. We see the value of our time and days. May we use our time wisely!
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