Verses 7-12 speak of the Son's redemption. Although God loves us and chose and predestinated us to be the objects of His grace, we became fallen soon after we were created. Because of this we needed redemption, which was accomplished for us by God in Christ through His blood (v. 7).
The redemption of the Son is through the blood that He shed for our sins on the cross (1 Pet. 1:18-19). Because the all-inclusive death of the Son on the cross has satisfied God's righteous requirement, His blood has become the means for our redemption.
Ephesians 1:13-23 speaks of the sealing and pledging of the Spirit. The Father is the source, the Son is the expression, and the Spirit is the reaching forth. The Father as the source chose and predestinated us in eternity according to His plan. The Son as the expression accomplished redemption in time according to the Father's plan, and the Spirit as the reaching forth becomes our seal and pledge to apply what the Son has accomplished of the Father's plan.
Today we have heard the word of the truth, which is the gospel of our salvation, and have believed into Christ and have been sealed in Him by the promised Spirit (v. 13). Once we have been sealed by the Holy Spirit, the seal will never fade away and will never be lost. But the sealing of the Spirit, which is the anointing of the Spirit in us, is not something that happens once for all. On the contrary, the sealing work is going on continually. The seal was put into us at the time we believed, but the sealing has continued from that time until now. It will continue until the day of the redemption of our bodies (v. 14). The Holy Spirit is the seal, and He is also sealing. He continues to do the work of sealing in us.
This sealing will spread from our spirit to our mind, emotion, and will. We have to admit that our soul has not been fully saturated. Even if our soul is saturated, our body has not been sealed. We need to be sealed continually, until our whole being is saturated. We are like a piece of paper or a cotton ball. When we received the seal of the Spirit, this piece of paper or cotton ball began to be saturated and permeated. Today, the sealing Spirit as the seal is sealing everything of the all-inclusive Christ, all that He has attained and obtained, into us (vv. 19-22). The result is that we all become one. This is the church, the Body of Christ, the fullness of the One who fills all in all (vv. 22b-23).