What are your obligations in imparting religious knowledge you just gained?

I have a question but I feel that I have to provide some background info first, so here goes: I have just started learning more about Islam and I'm at a point where whenever I learn something new I tell the members of my family. My thinking so far has been that I'm duty bound to tell them in case they didn't know. And sometimes I catch my self being surprised that a member of my family already knew this thing I'm telling them and they actually expand on it. I'm thankful of course that I gained this extra knowledge but that initial feeling of surprise is a sign of ego. I learned this from this video by Nouman Ali Khan. http://www.youtube.com/watch?v=xtjwtmjbOKE Sometimes the advice that I give also comes out sounding judgmental and annoys the person I'm giving the advice to and I want to leave the person alone but I feel since I have been blessed with this opportunity to learn more about Islam I should try to help that person do the same. Honestly, the issue isn't about the particulars of this "journey of Islamic discovery" as mentioned in the clip above, it's more about getting them to start the journey. This is a long winded explanation of what the problem is before I ask the question, but basically what I'm wondering is what are my obligations of imparting any new knowledge I'm blessed with in regards to Islam for the main purpose of getting members of my family interested enough to search more on their own? Can I just concentrate on learning now? Please provide the hadith/source you got your answer from. Jazaka Allahu Khairan