The author to the Hebrews shows us that Christ is far superior to Moses. Christ is the Son who is the master over the household of God, while Moses, although he was a faithful servant, is still only a servant in the household. We see that Christ is the one who built the house because He is God (who is the builder of all things) and because His work of redemption is the only foundation that such a house could be built on. Moses, on the other hand, is only a stone in that house.
We can know that we are a part of that house, that we are saved, by holding on to Christ. We do so by using the means of grace that He gives us: the Word, prayer, the sacraments, and also by persevering in holiness. God Himself will give us the grace to do this if we are trusting in Him.