Ramban on Shemos 2:11

English: AND WHEN MOSES WAS GROWN UP HE WENT OUT UNTO HIS BRETHREN. This is to be understood that he grew to manhood. It has already been said, And the child grew , 80 Verse 10. which means that it was no longer necessary to wean him, and then the mother 81 Verses 8-9: And the maiden went and called the mother of the child , etc. brought him to Pharaoh’s daughter, and he became her son , 80 Verse 10. for he was to stand in the presence of kings. 82 See Proverbs 22:29. After that, he grew to manhood in maturity of mind. AND HE WENT OUT UNTO HIS BRETHREN. This indicates that they told him he was a Jew, 83 See Esther 3:4. and he desired to see them because they were his brethren. Now he looked on their burdens and toils and could not bear [the sight of his people enslaved]. This was why he killed the Egyptian who was smiting the oppressed Hebrew.