וַיְהִ֕י מִקֵּ֖ץ אַרְבָּעִ֣ים שָׁנָ֑ה וַיֹּ֤אמֶר אַבְשָׁלוֹם֙ אֶל־הַמֶּ֔לֶךְ אֵ֣לֲכָה נָּ֗א וַאֲשַׁלֵּ֛ם אֶת־נִדְרִ֛י אֲשֶׁר־נָדַ֥רְתִּי לַֽיהוָ֖ה בְּחֶבְרֽוֹן׃
Setelah genap empat puluh tahun, Absalom berkata kepada raja, “Izinkanlah aku pergi untuk membayar nazarku yang telah kunazarkan kepada Yang Mahakekal, di Hebron.”
Rashi
At the end of forty years. [After] Yisroel had asked Shmuel for a king this rebellion and weakening of the kingdom occurred.2This is the opinion of Rebe Nehuroi in the name of Rebbe Yohoshua brought in Temurah 14b. Rashi is explaining that these forty years are not describing how long Avsholom was engaged in his intriguing against the king. Rather, the verse is informing us that forty years after their improper request, the kingdom was weakened.
Rashi
And fulfill the vows [of bringing sacrifices] Our Rabbis said, "[Avsholom wanted] to bring lambs from Chevron3Ibid. because there, the lambs were fat."4Rashi there brings the Talmud in Menachos 87a that discusses the quality of the lambs of Chevron.