1) Literally the ''quasi-seven'', an abridged form of the 7 blessings making up the Shabbat amida. 2) Even though there is no obligation for the chazan to repeat the Shemoneh Esreh of the evening prayers, the Rabbis made a special ruling for that of Shabbat. In Talmudic times, the synagogues were usually situated in the fields outside the city, and it would be dangerous for individuals to be left there alone; consequently, the Rabbis added this special blessing to the end of the service in order to delay the completion of the prayers, thus allowing the latecomers to catch up and then leave the synagogue along with the rest of the congregation. This enactment is still binding today, even though the reason for its creation no longer applies. 3) Each phrase of the abridged version parallels one of the seven blessings in the Shemoneh Esreh of Shabbos: ''a shield to our fathers'' = ''the shield of Abraham'' (1st blessing), ''revives the dead'' = ''revives the dead'' (2nd), ''the holy G-d'' = ''the Holy G-d'' (3rd), ''He gives rest to his people'' = ''be pleased with our rest'' (4th), ''we will serve Him'' = ''Be pleased, Lord our G-d'' (5th), ''to his name we give thanks'' = ''We thank You'' (6th), ''the Lord of peace'' = ''O grant peace'' (7th). 4) The Tur quotes a story from ''Sefer Chasidim'' which tells of a certain Chasid who saw another previously deceased Chasid in his dream, who had a very sickly and pale appearance. In the dream, he asked the man why he looked so terrible, and the man answered that it was because he used to talk in synagogue on Friday night during ''The heavens and earth were finished...'' the abridged version of the Shemoneh Esreh, and during Kaddish (See Mishna Berurah 268:26) 5) The chazan then repeats aloud what the congregation have just said. 6) In other words, neither he, nor the congregation as a whole, may say the blessing at the beginning or the end of that group of phrases, because the blessing was only enacted for the chazan.

1) On a festival that falls on the Shabbat. 2) When Shabbat follows the festival, the people are not working and so came to the synagogue on time. However, this blessing is still said, even though there are no latecomers, because of the principle of ''Lo Ploog'' (no differentiation), meaning that when the Sages made an enactment, it applies across the board, even in cases where the reasoning behind the enactment doesn't apply.

בכל שבתות השנה אומרים ברכה זאת אפילו ביום טוב ובשבת שחל לאחר יום טוב אך כשחל יום טוב ראשון של פסח בשבת אין אומרים אותה

1) This also includes a house where a minyan regularly gathers for prayers, as long as they have a Torah Scroll with them (Mishna Berurah 268:24). 2) The week of feasting held for a bride and groom after the wedding in different people's homes, which includes Shabbat as well. 3) Where the mourners sit for a week and are comforted by relatives and friends coming to visit them. 4) These sort of places were never included in the original ruling, because the reasoning, based on concern for latecomers, doesn't apply. The Magen Avraham writes that those who have the custom to say the blessing even in places where there is no regular minyan, should not be stopped or told off. However, the Pri Megadim disagrees because of the concern that saying it in these places might constitute a blessing in vain.