Paul informs the Ephesians of his request to God on their behalf. After describing who “the Father” is, Paul expresses what he wants the Father to grant to these people, namely that they may be strengthened to comprehend all the minute features of “the love of Christ” (Ephesians 3:14-19).
The strength Paul is wanting God to grant to the Ephesians will come through their faith. In a time before the New Testament was completed, and people could read what was revealed, Paul is asking God to communicate to the Ephesians, and other churches as well, what they will need to help them comprehend all the different aspects of “the love of Christ.” The faith of these Ephesians would then be increased, because they have heard what was spoken by those to whom God revealed His message.