Paul writes in Ephesians 1:13-14, “In whom you also trusted, after that you heard the word of truth, the gospel of your salvation: In whom also after that you believed, you were sealed with that Holy Spirit of Promise, which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of His glory.”
Notice the progression: first, we believed after we heard the word. After heard and believed, we were sealed. Then, the Holy Spirit was given to us (John 3:6; Ephesians 1:13) to be earnest of our inheritance. Since he bought us with a price (I Corinthians 6:20). He keeps us unto the day of redemption for His glory (Ephesians 1:14).