Reposted from 2011:
Read Ephesians 1 at Bible Gateway.
Previously: Ephesians 1:3-6, predestined and accepted
In Him you also trusted, after you heard the word of truth, the gospel of your salvation; in whom also, having believed, you were sealed with the Holy Spirit of promise, who is the guarantee of our inheritance until the redemption of the purchased possession, to the praise of His glory. Eph 1:13-14
The baptism of the Spirit we were baptized with was meant to seal us. Look at it this way, our redemption occurred at the resurrection of Jesus Christ, in 30-33 AD. It was applied to us the day we bowed our knee to the LORD and placed our faith in Jesus Christ 2000 years later (or whatever the date was). But we will not inherit all that God has proclaimed will be ours, until the Lord Jesus returns. He has said, okay, now you have eternal life. Have we inherited eternal life? Not really – we are still living in this world, with sin and death working in our flesh. He has said, now you are princes and princesses of the King of the Universe. But have we inherited the exalted status to which our rank entitles us? No – we are ground underfoot by the kings of this world.
Because there is a delay, from the date we received our spiritual blessing (Eph 1:3) and the date we will receive the attached manifest blessing, God gave us His pledge, His collatoral that He will pay in full on the due date. The LORD’s pledge, is the Holy Spirit. The fact that we have Him, is God’s guarantee that all that He says He will do, will happen to us.
Here is another way to look at it. Passover and Unleavened Bread are the spring feast days which teach that we have been redeemed from the kingdom of darkness and cleansed of sin (just as we cleanse our homes and our bodies of yeast, which symbolizes sin). The next feast day is Pentecost in Greek, or Shavuot in Hebrew. On the day of Pentecost, God gave the two tablets of stone to Moses with His Law inscribed on it. On the day of Pentecost, God poured out His Spirit on to the Church in Act 2 (Eze 36:26-27 teaches us that God’s Law will be written on the tablets of our hearts by His Spirit.) The Spirit is our seal. The fall feast days are Trumpets, Atonement, and Tabernacles, which proclaim the Second Coming of the Lord Jesus — His return, at which we will receive our full inheritance.
So we were first washed (spring), then sealed (summer) so that what God has put in us — His life, new life by His Spirit — will be preserved until the day we receive it (fall). First we wash the jam jar, sterilizing it of every trace of bacteria. Then we pour the jam in the clean vessel. Then we seal the jar so that no new bacteria can enter in to contaminate the contents. Then the jam is preserved for the day we open the jar to enjoy its contents. It is exactly the same picture that God has done for us!