I am convinced of mine just as you are of yours. Faith is always involved. The Vedas state that this knowledge was first imparted by the Supreme Lord to Brahma. Then Brahma spoke it so another, and them to another, and in this way it has been passed down. There is no empirical way to prove this succession, but one is either convinced or they are not. I think part of it, for me, is that I've always looked for the basic philosophical points of the theist in general. I found that the Vedas applied these points further and more consistently than anything else I had come across. That is just my experience. In any case, the goal is love for God. With that all else becomes meaningless (or, rather, is realized as being meaningless). I may believe one thing and you may believe another, but all we can really do is keep toward that goal.