וַיִּקַ֥ץ שְׁלֹמֹ֖ה וְהִנֵּ֣ה חֲל֑וֹם וַיָּב֨וֹא יְרוּשָׁלִַ֜ם וַֽיַּעֲמֹ֣ד ׀ לִפְנֵ֣י ׀ אֲר֣וֹן בְּרִית־אֲדֹנָ֗י וַיַּ֤עַל עֹלוֹת֙ וַיַּ֣עַשׂ שְׁלָמִ֔ים וַיַּ֥עַשׂ מִשְׁתֶּ֖ה לְכָל־עֲבָדָֽיו׃ (פ)
Salomo erwachte; es war ein Traum. Er ging nach Jerusalem und stellte sich vor die Bundeslade des Herrn; dort opferte er Ganzopfer und Mahlopfer und bereitete ein Mahl allen seinen Dienern.
Tze'enah Ure'enah
“Then Solomon awoke; it had been a dream” [3:15]. Solomon woke up from his sleep and understood the dream that he had dreamed. He was happy and went to the city of Jerusalem and brought burnt offerings and peace offerings. He rejoiced with his servants and he made a great banquet for them. Our sages say that he awoke from his dream in which God had promised him in the dream that he will give him great wisdom. When he woke up from the dream, he heard a bird singing, and he understood what the bird was saying. Solomon saw that the Holy One had given him the wisdom to understand the language of the bird.1Ecclesiastes Rabbah, 1.1.
Rashi
Shlomo woke up and behold it was a dream. And behold he understood that his dream was true. He heard a bird chirping and understood its language, a dog barking and he understood its language.
Rashi
And [he] made a feast. Out of his heart’s happiness [he celebrated] because he realized that his dream was true.24Shlomo celebrated his newly acquired wisdom. Rabbi Elazar said that from here we derive the custom of making a festive meal [e.g., siyum] to honor the completion of reading the Torah or studying a Masechta. See Shir Hashirim Rabboh 1:9.