Hebrews 3:1-6 (ESV)
Therefore, holy brothers, you who share in a heavenly calling, consider Jesus, the apostle and high priest of our confession,  who was faithful to him who appointed him, just as Moses also was faithful in all God's house.  For Jesus has been counted worthy of more glory than Moses—as much more glory as the builder of a house has more honor than the house itself.  (For every house is built by someone, but the builder of all things is God.)  Now Moses was faithful in all God's house as a servant, to testify to the things that were to be spoken later,  but Christ is faithful over God's house as a son. And we are his house if indeed we hold fast our confidence and our boasting in our hope.
“But Christ is faithful over God’s house as a son, and we are his house if indeed we hold fast our confidence and our boasting. “ These days we don’t use the term house this way much. Here in America a house is a building people live in, and that is about it. We don’t refer to families as houses. But this is I believe the way the word is being used here. Something akin to the way house is used in “The Fall of the House of Usher” or the House of Windsor. It is a term used for royal or noble families. And we are his house. Moses was a servant in this house. Nothing more. Servants are directed by the law. They don’t have a choice. Someone tells them what to do and when. Jesus though is faithful over all things as a son. Sons in the noble houses take responsibility over the house, direct the servants, etc. not because of the law, but because of vested interest. So Jesus takes over out of his own free will, faithfully watching over everything. And we become part of this house, adopted into this royal family through faith in Jesus holding fast our confidence and our boasting in our hope. Boasting in Christ who is our confidence.