[He has also appropriated and acknowledged us as His by] putting His seal upon us and giving us His [Holy] Spirit in our hearts as the security deposit and guarantee [of the fulfillment of His promise].
2 Corinthians 1:22 (AMP)
The Holy Spirit is God’s security deposit! This means it is actually the Holy Spirit’s job to guarantee that God’s purposes for our lives will come to pass. And so what is required of us is that we learn to live lives of complete dependence on Him where we no longer rely on our own efforts and performance, but we trust the unfailing working of the Spirit of grace in us.