How do we know that God builds His house?

In 2 Samuel 7:8, God reminds David that He is the one who took him from a humble position and made him a ruler. This illustrates that it is God who calls and establishes His people, not their own efforts. Just as God chose David, He chooses His people and builds them into a spiritual house, emphasizing that any advancement and security we have comes solely from His action and grace. We do not add to His work; rather, He has accomplished it all through Christ, establishing us as part of His household.