Paul returns to where he left off in verse 1 and begins to pray. ″For this reason″ probably refers to the contents of Ephesians 2 as well as 3:12 (we have prayer access to God through Christ).

The apostle kneels before the Father and marvels that His whole family is one, derived from His name and extending across heaven and earth. God's wisdom, grace, and power are indeed stupendous in forging one family out of such disparate and divided individuals and nations.

The prayer is Trinitarian. Paul prays that the Father will strengthen the ″inner being″ of the believers with the power of the indwelling Spirit (Ephesians 3:16). God has limitless and glorious riches from which He can do this. What God does inside us forms the basis for what He then does through us. Many Christians ignore what is on the inside and live out only an external and ritualistic kind of religion.

When God strengthens us through His Spirit, it leads to our hearts becoming the dwelling place for Christ, who lives (in Greek, this means ″permanently reside″) in us (v. 17). The life of Christ will then be seen in and through us. We will experience Christ's marvellous love, although we will never fully sound its depths. We can spend an eternity discovering how wide (He died for all), how long (eternal), how high (beyond the reach of any foe), and how deep (reaching down to the most depraved) His love for us is (v. 18). These four dimensions are interrelated and bring out the perfect love of Christ.

Indeed, this love of Christ ″surpasses knowledge″ (v. 19). Paul marvels at how God's divine love, which leads us into right relationships with Him and one another, is far superior to any human knowledge or religion.

Paul prays that the believers would be deeply rooted (like a tree) and grounded (like a building) in this love (v. 17) and thus be ″filled to the measure of all the fullness of God″ (v. 19). This is the goal. We know we are full of God when we are full of His love (1 John 4:8). This is Christian maturity, both for individuals as well as the church (″together with all the Lord's holy people″; Ephesians 3:18).