“And to know the love of Christ, which passeth knowledge, that ye might be filled with all the fulness of God.”
King James Version (KJV)
3:19 And to know - But the apostle corrects himself, and immediately observes, it cannot be fully known. This only we know, that the love of Christ surpasses all knowledge. That ye may be filled - Which is the sum of all. With all the fulness of God - With all his light, love, wisdom, holiness, power, and glory. A perfection far beyond a bare freedom from sin.
Eph 3:19 And to know the love of Christ, which passeth knowledge. This is one of Paul's paradoxes, like 1Ti 5:6. They could know something of the love of Christ, but we can never fully comprehended the infinite. That ye be filled with all the fulness of God. Filled with God's grace to the full.