A foretaste is an advance taste or realization. The Bible calls it an earnest—"the earnest of our inheritance" (Ephesians 1:14). It means to bring a taste of the whole before we have the whole. Our inheritance is Christ himself—and the Holy Spirit brings us into his very presence as a foretaste of being received as his bride, enjoying everlasting love and communion with him.
Paul describes a people of God who are "sealed with that Holy Spirit" (Ephesians 1:13). This speaks of a people specially marked by a work of the Spirit. The Holy Spirit has produced in them a distinguishing mark, a glorious inner work—something supernatural that has changed them forever.
They are not ordinary believers anymore. They are no longer "of this world," since they have set their affections on things above, not on the things of this earth. They are not moved by the world's events; rather, they are unshakable. They are no longer lukewarm or halfhearted. Instead, their hearts cry out night and day, "Come quickly, Lord Jesus…."
What happened to them? What did the Holy Spirit do in these believers? What marked and sealed them forever as the Lord's possession? Simply this: The Holy Ghost gave them a foretaste of the glory of his presence! He came to them, rolled back heaven—and they experienced a supernatural manifestation of his exceeding greatness! He gives us "a little heaven" to go to heaven with—a whetting of our appetite.
What kind of bride do you think the Spirit will present to Jesus Christ on that day of revelation? One who is halfhearted? Whose love is lukewarm, or cold? Who is not devoted to Jesus? Who does not want intimacy with Christ?
If you truly love Jesus, he's never out of your mind. He is present in your every waking moment. Some Christians think, "That will happen after I die. When I get to heaven, everything will change. I'll become the special bride of the Lord then." No, dying doesn't sanctify anybody! This Holy Ghost is here today. He is alive and working in you—to produce in you a passionate love for Christ on this side of death!
Romans 8:26 describes one of the most powerful works of the Holy Spirit in the heart of the believer. "Likewise the Spirit also helpeth our infirmities: for we know not what we should pray for as we ought: but the Spirit itself maketh intercession for us with groanings which cannot be uttered."
The Greek word used for groaning means "a yearning"—a longing for more of Christ. You can yearn after Jesus so much that you sit in his presence and nothing comes out but a deep groaning—something that cannot be uttered. It says, "Jesus, you're the only happiness there is in this world. I have tasted and seen that you're good—and I want all of you."
This is the mark of one who is walking in the Spirit. He has an insatiable appetite for Jesus. Like Paul, he is just anxious to depart and be with the Lord!