וְשָׁ֨ם אִתָּ֜נוּ נַ֣עַר עִבְרִ֗י עֶ֚בֶד לְשַׂ֣ר הַטַּבָּחִ֔ים וַנְּ֨סַפֶּר־ל֔וֹ וַיִּפְתָּר־לָ֖נוּ אֶת־חֲלֹמֹתֵ֑ינוּ אִ֥ישׁ כַּחֲלֹמ֖וֹ פָּתָֽר׃
Y estaba allí con nosotros un mozo Hebreo, sirviente del capitán de los de la guardia; y se lo contamos, y él nos declaró nuestros sueños, y declaró á cada uno conforme á su sueño.
Or HaChaim
In due course Joseph was proven right, for ultimately the chief butler did recall him and this started Joseph's dramatic rise to power. The reason Joseph was punished was because he imagined that his own advancement would depend on the goodwill of the chief butler. While G'd did use the chief butler as His instrument in advancing Joseph's fortune, the chief butler did not act voluntarily. He was prompted by fear to recall his days in jail (41,12). Joseph had to be taught the lesson not to rely on man.
Sforno
49,23. וישטמוהו בעלי חצים, The expression בעלי חצים means: “the slanderers.” The word חץ, usually meaning “arrow,” is used as a simile for slander in Jeremiah 9,7חץ שחוט לשונם, “their tongues are like a sharp arrow.” One of these slanderers was the chief of the cup bearers when he referred to Joseph as נער עברי עבד, three words which are each a derogatory term. (41,12). Also some of Pharaoh’s servants are included in the list of those who slandered Joseph. They are reported as commenting with disdain that “Pharaoh has appointed a slave who had been sold for 20 pieces of silver as our ruler.” (Sotah 36).