No matter if we have a master or not, we must rely on ourselves, because the highest master is ourselves rather than the Master outside or the Master inside. However, before reaching a certain high level, we still need the guidance from a wise person whom we call Master or Teacher.
Of course, before we achieve anything in spiritual practice, we still need to rely on someone who has more experiences than we do, just like we need a guide to lead the way, because we haven't treaded on that path before and don't know what hindrance or danger there will be on the way. Therefore there should be a guide to lead us, and we will know everything after we walked this path. The guide is just to lead the way, but we have to walk on our own. After we finish it, we need to come back and lead others, instead of being led each time on the same path.