Moshe grew up in the house of Paroh and became an adult. Verse 12: “and he saw them [the Jews] in their suffering.” RASHI: He made himself aware of it. He could have been oblivious, busy with partying and shopping. He went out and looked for it, to be aware of it.
When we talk about Moshe growing up, we see two verses that seem to repeat that fact. In the second verse when it tells us that Moshe grew, we are then introduced to the fact that he went to see the suffering of his people. The second verse is not talking about physical development – it is talking about Moshe becoming a mature adult. A child and a teen are very egocentric – focused on themselves, their needs, their wants. We know someone is growing up and maturing when they are able to see other people’s sufferings and want to help other people. When your focus is outwards not inwards, when you worry about the other person and not yourself, that’s when you know you’ve finally grown up.
And, if you want to see this concept explained in a way more profound way, get the book Holy Woman by Sara Yocheved Rigler. http://www.sararigler.com/books-holywoman.php