Ben Ish Chai on Yosef's Name and Prophecy

בן איש חי – 37:19 “ויאמרו איש אל אחיו, הנה בעל החלומות הלזה בא” – “And the brothers said to one another, look, that dreamer is coming.” The brothers didn’t realize it, but they had Ruach Hakodesh and they were prophesizing that in the future, the Malach Gavriel would add the letter, “ה'” to Yosef’s name, as the Posuk in Tehillim spells Yosef’s name that way – 81:6 “עדות ביהוסף שמו”. The Gemara in Sotah 10b says that the Malach Gavriel is the appointed Malach over dreams, and that is what the words of the Posuk are referring to here, “הנה בעל החלומות” – the one in charge of dreams – Malach Gavriel, “הלזה בא” – “ 'ה – לזה בא” will be adding the letter ה' to the one who is coming, to Yosef.