The Spirit Himself bears witness with our spirit that we are children of God.
It is impossible to perceive all that became ours when we were born again. There is no way we can understand all that heaven is like. How could we ever comprehend all that is ours as fellow heirs with Christ? The knowledge that we will share Christ’s inheritance with Him absolutely astounds us! Left to our own, we could not begin to understand all that we received once we became children of the King. The Holy Spirit convinces us that we are indeed children of God and helps us understand the riches of our inheritance.
Perhaps you did not have a loving father. The Spirit’s role is to teach you how to respond to a Father who relates to you only in perfect love and how to live like a child of the King. Perhaps you grew up in poverty. The Spirit will show you the inexhaustible riches available to you as a child of God. If you were simply declared an heir and then left on your own, you could not begin to use your inheritance. But the Father has given you His Spirit to serve as your Guide and Teacher. The Holy Spirit will lead you to the magnificent promises and resources that became available when God adopted you into His family. Take time to meditate on the wonderful promises of God that are available to you. Let the Holy Spirit convince you of the reality that you are, indeed, a child of God and a fellow heir of Christ.