Soncino English Talmud
Shabbat
Daf 87b
[In respect] of their encamping. R. Aha b. Jacob said: [In respect] of their journeying. Now, they disagree about [the precept of] the Sabbath [as communicated to them at at Marah, for it is written, [Observe the Sabbath day …] as the Lord my God commanded thee, whereon Rab Judah commented in Rab's name: As he commanded thee at Marah. One Master holds: They were commanded concerning the Sabbath [in general], but not concerning tehumin. Whilst the other Master holds: They were commanded concerning tehumin too. Come and hear: As to the Nisan in which the Israelites departed from Egypt, on the fourteenth day they slaughtered their Passover sacrifices, on the fifteenth they went forth, and in the evening the first-borns were smitten. 'In the evening': can you think so! Rather say, The first-borns having been smitten the [previous] evening, and that day was a Thursday. Now, since the fifteenth of Nisan was on a Thursday, the first of Iyar was on the Sabbath, and the first of Siwan was on a Sunday, which is a difficulty according to the Rabbis? — The Rabbis answer you: Iyar in that year was indeed made full. Come and hear that they did not make it full! As to the Nisan in which the Israelites departed from Egypt, on the fourteenth they killed their Passover sacrifices, on the fifteenth they went forth, and in the evening the first-borns were smitten. 'In the evening' can you think so! Rather, say, The first-borns having been smitten since the [previous] evening, and that day was a Thursday. Nisan was a full month, so that [the first of] Iyar fell on the Sabbath. Iyar was defective, so that [the first of] Siwan fell on a Sunday. This is a difficulty according to the Rabbis? — That agrees with R. Jose. R. Papa observed, Come and hear: And they took their journey from Elim, and all the congregation of the children of Israel came unto the wilderness of Sin … on the fifteenth day of the second month. Now that day was the Sabbath, for it is written, and in the morning, then ye shall see the glory of the Lord, and it is written, six days ye shall gather it. Now, since the fifteenth of Iyar was on the Sabbath, the first of Siwan was on a Sunday, which is a difficulty according to the Rabbis? — The Rabbis can answer you: Iyar of that year was made full. R. Assi of Hozna'ah said to R. Ashi, Come and hear: And it came to pass in the first month of the second year, on the first day of the month, that the tabernacle was reared up; [and with reference to this] a Tanna taught: That day took ten crowns. It was the first of the Creation, the first for the princes, the first for the priesthood, the first for [public] sacrifice, the first for the fall of fire [from Heaven], the first for the eating of sacred food, the first for the dwelling of the Shechinah in Israel, the first for the [priestly] blessing of Israel, the first for the interdict of the high places, [and] the first of months. Now, since the first of Nisan of that year was on a Sunday, that of the previous year must have been on a Wednesday. For it was taught: Others say, Between one 'Azereth and another, and between one New Year['s day] and another, there can be a difference of only four days, and in a leap year, five [days]. Hence the first of Iyar must have fallen on the eve of the Sabbath [Friday], and the first of Siwan on the Sabbath, which is a difficulty according to both R. Jose and the Rabbis? — In R. Jose's view, seven months were declared defective;
Sefaria
Mesoret HaShas