How do we know that God has saved His people?

God's saving work is made evident through the fulfillment of His promises and the transformative power of the gospel in the lives of believers. Acts 2 recounts the day of Pentecost when the Holy Spirit filled the apostles, resulting in the salvation of 3,000 souls. This is a direct fulfillment of God's promise to build His church and calls to mind Isaiah 66:14, where the sight of God's work brings rejoicing to His people. The presence of spiritual fruits and the testimony of changed lives serve as evidence that God has indeed saved His people and continues to do so.