Where was Besu'el?
Rashi: Besu'el wanted to hold her back, so an angel killed him.
Targum Yonason: At night, Besu'el ate from the food [intended for Eliezer, in which they placed poison 1 ], and they found Besu'el dead at dawn.
Ibn Ezra: He was quiet; he did not receive gifts. Perhaps Lavan was greater than his father in Chachmah and honor. We find that he spoke up before him (verse 50).
What did they mean by "days or ten"?
Rashi: "Days" means a year (as it generally does in the Chumash), and "Ten", ten months.
What was the reason for the suggested delay?
Rashi: It was customary to give Besulos a year to prepare for the wedding.
Seforno: To give Rivkah a chance to get used to the idea of such a major change in her life - a new country and a new lifestyle.
Why are they now asking to delay? The day before they had declared 'Take her and go!'?
Chizkuni: Initially, they did not know that he was a Shali'ach to be Mekadesh. Therefore, they said 'take her to Yitzchak to be Mekadesh her.' After they saw that Eliezer was Mekadesh her, they requested the year given to a Besulah to prepare for Chupah.
Alshich: Lavan saw the ornaments she received for giving water, and expected even more for giving a meal. He said "Kach va'Lech", expecting great gifts in return. Eliezer gave esteemed gifts to Rivkah, and mere Peros to Lavan and his mother. Lavan said that she will delay to anger Eliezer, or so he will correct his injustice. And after the delay, she will go
The Gemara (Nedarim 37b) says that "Acher Telech" is Itur Sofrim; it is a tradition from Sinai. What is this?
Ran (37b) #1: They are extra words 1 to beautify the expression.
Ran (37b) #2: They are changes [from the simple way to write] to beautify the expression.
Ran (37b) #3: They are Ta'amim (notes) that interrupt in the verse. Me'iri (37b) - even though the Gemara mentioned also Pisuk Ta'amim, that refers to notes that separate matters, e.g. Asnachta and Zakef. Itur Sofrim are other notes.
Rosh (37b): They are letters that should have been written, but were removed. It should have said 'v'Achar'.
Birkas Avraham (37b): Why is this called tradition from Sinai? It is part of the tradition of the text of the Torah! This requires investigation. Igros Moshe (OC 4:24), Sedei Tzufim 37b