“In him you also, when you heard the word of truth, the gospel of your salvation, and believed in him, were sealed with the promised Holy Spirit, who is the guarantee of our inheritance until we acquire possession of it, to the praise of his glory.” – Ephesians 1:13–14 (ESV)
These days when a house is bought and ownership changes, there is generally first an amount of money put into and account to guarantee the earnestness of the buyer. Remember when we first learned the doctrines of grace? At first we did not know much about saving grace. We did not know whether God had converted us, or we had converted ourselves. As we read and listened to Bible teaching, we began at once to see how God the Father planned, and God the Son carried out the plan, and God the Holy Spirit made the plan effective. We learned truths which we might have believed before, but which we could not clearly and fully understand. The joy of gaining the knowledge of God’s truth was exceeding great. Having got a hold once and for all of the truth of God in that moment His Holy Spirit increased our knowledge, and opened the eyes of our understanding, we had the earnest, the guarantee, that we were promised. One day shall see, not through a glass darkly, but face to face, and then we shall know the whole truth, even as we are known now by God.