(Mishnah): A Besulah (virgin) is married on Wednesday, and a widow on Thursday.

[The first law] is because in cities, Beis Din meets on Mondays and Thursdays. If he has Ta'anas Besulim (the Chasan found that she is not a Besulah), he will go promptly to Beis Din the next morning.

(Gemara - Bar Kaparah): [The law of our Mishnah] is because Brachah is written [in Ma'aseh Bereishis] on these days.

Question: Brachah is written only on Thursday and Friday - on Thursday is the Brachah to birds and fish, and on Friday is the Brachah to Adam and Chavah!

Answer (R. Yosi): Bar Kaparah holds that [in our Mishnah] 'Wednesday' is Wednesday night (which begins Thursday), and 'Thursday' is Thursday night (which begins Friday. The custom of which day to marry is primarily due to Brachah. The Mishnah explains why men who marry Besulos preferred Wednesday over Thursday. If not for Beis Din, due to Brachah all would prefer Thursday, due to the Brachah to man.)

Question: Brachah is written on the seventh day!

Answer: Brachah [on Shabbos] is not written for the creations, only for the day.

Inference: This is because Brachah is not written for the creations, only for the day - but if it were written for the creations, she would get married on Shabbos.

Question: A Beraisa taught unlike this! One may not have the first Bi'ah (i.e. with a Besulah) on Shabbos, for he makes a wound.

[We needed to answer that Brachah on Shabbos is not written for the creations] according to Acherim, for Acherim permit [the first Bi'ah on Shabbos].

Objection: Acherim permit only when he entered [her into his Reshus before Shabbos]. Before he entered her, he did not merit her Metzi'ah, earnings and annulling her vows. After entering her, he merited her Metzi'ah, earnings and annulling her vows;

If you will say so (that he may enter her on Shabbos), it turns out that he acquires a Kinyan on Shabbos! (SEFER NIR - the Yerushalmi holds that the Brachah applies to one who enters her on that day, so we do not ask that he could enter her on Erev Shabbos and have Bi'ah with her on Shabbos.)

Inference (R. Mana): These who enter a widow on Friday, must enter her during the day, lest he be like one who acquires a Kinyan on Shabbos.