Today's daf is sponsored in honor of Ariel Bruce on her birthday. "A wonderful daughter, wife, and mother of three beautiful, strong, sweet children. May this year bring you only happiness and peace to Kol Yisrael. All our love, Saba, Steve and Savta Lisa." 

Today's daf is sponsored by Rebecca Darshan in memory of (lilui nishmat) Helene Isaacs, her mother, on the occasion of her 25th yahrzeit. "She encouraged women's learning and especially loved learning in Jerusalem during the last 10 years of her life. Her life was too short in years, but full every day."

The Mishna delineates different possible oaths of expression (shevuot bitui), both those relating to future actions and past actions. Rabbi Yishmael does not hold that past oaths are considered oaths of expression for which one would be liable to bring a sacrifice. Oaths can apply to intangible matters, whereas vows cannot. However, vows can apply to a mitzva while an oath cannot, as one can render the object of a mitzva forbidden, such as a sukka, through a vow.

Rav and Shmuel disagree about a case where one takes an oath that someone else threw or didn't throw a stone in the sea. Rav holds the oath is valid as it can be stated in both the positive and negative formulations. Shmuel holds the oath is invalid as it cannot be stated in the future, as one cannot take an oath regarding an action that is out of one's control, and whether or not someone else will throw a stone or not is out of one's control.

The Gemara makes two attempts to connect the debate of Rav and Shmuel to a tannaitic debate, but both attempts are unsuccessful.

The Gemara raises two difficulties on Shmuel's opinion from tannitic sources but resolves both difficulties.

Why did the Torah create a different category for a shevuat haedut, one who withholds testimony, if it could have been considered an oath of expression? Rava and Abaye have different approaches to understanding the connection between the two categories.