In Christ, as Paul continues his praise, these believers in particular are among those who hoped. So, “you also” are part of the drama. The time sequence of blessing is this: “you also, having heard [i.e., when you heard] the message of truth, having [or when you] also believed, you were [at that time] sealed.” The hearing and the believing logically were necessary for the sealing, and in timing they occurred together. The word “sealed” was used to signify the authority of the one whose seal it was,