Ephesians 1:12-13

so that we who were the first to hope in Christ [who first put our confidence in Him as our Lord and Savior] would exist to the praise of His glory. In Him, you also, when you heard the word of truth, the good news of your salvation, and [as a result] believed in Him, were stamped with the seal of the promised Holy Spirit [the One promised by Christ] as owned and protected [by God]. [John 7:39; Acts 2:33]