Paul's writing this letter for this flesh age of time about the favor of God through Christ.
3 How that by revelation he made known unto me the mystery; (as I wrote afore in few words,
This revelation that made known the mystery to Paul is referenced in; Romans 16:25 Now to him that is of power to stablish you according to my gospel, and the preaching of Jesus Christ, according to the revelation of the mystery, which was kept secret since the world began, "Was" secret but is now known by those of us that seek Truth. God has opened up everything we need to know. The secret starts in Genesis but is opened in Matthew 13:35 That it might be fulfilled which was spoken by the prophet, saying, "I will open my mouth in parables; I will utter things which have been kept secret from the foundation of the world." Study The parables of God and sight will be given to you. Do you know about "the tares of the field"? Study Matthew 13.
4 Whereby, when ye read, ye may understand my knowledge in the mystery of Christ)
Romans 16:26 But now is made manifest, and by the scriptures of the prophets, according to the commandment of the everlasting God, made known to all nations for the obedience of faith: To have faith, you must give yourself to God and by giving yourself, you must study His letter to you. Romans 10:17 So then faith cometh by hearing, and hearing by the word of God.
5 Which in other ages was not made known unto the sons of men, as it is now revealed unto his holy apostles and prophets by the Spirit;
This flesh age is for The Word and The Way of Christ Jesus. It was told in both The Old and New Testaments. You must open His Word. Nothing is hidden that those who seek Him won't be given.
6 That the Gentiles should be fellowheirs, and of the same body, and partakers of his promise in Christ by the gospel:
The Way is given to everyone. It's up to each of us to choose if we want to accept Him and His Way. John 3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
7 Whereof I was made a minister, according to the gift of the grace of God given unto me by the effectual working of his power.
As Paul saw himself in the past as the worse of the worse, he sees himself changed by the favor of God through the blood of Christ. The Holy Spirit filling him with The Truth and the ability to teach it.
8 Unto me, who am less than the least of all saints, is this grace given, that I should preach among the Gentiles the unsearchable riches of Christ;
Humility!
9 And to make all men see what is the fellowship of the mystery, which from the beginning of the world hath been hid in God, who created all things by Jesus Christ:
Christ gave Himself to every single human being, as far back as from the beginning of this age. 1 Peter 3:18-19 18 For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit: 19 By which also he went and preached unto the spirits in prison; "Prison" = those that have died and are on the other side of heaven from God. Luke 16:26 And beside all this, between us and you there is a great gulf fixed: so that they which would pass from hence to you cannot; neither can they pass to us, that would come from thence. "Gulf" = χάσμα chásma, khas'-mah; from a form of an obsolete primary χάω cháō (to "gape" or "yawn"); a "chasm" or vacancy (impassable interval):—gulf. a gaping opening.
10 To the intent that now unto the principalities and powers in heavenly places might be known by the church the manifold wisdom of God,
Paul's intent for this letter to the Ephesians is to inform everyone of the forces, both good and bad, earthly and heavenly of The Truth of God. Paul's talking to these "principalities" = rulers in heaven and earth. A strong teacher puts satan and his followers in their place without any fear.
11 According to the eternal purpose which he purposed in Christ Jesus our Lord:
That "eternal purpose" of course was His sacrifice for everyone to have The Way to eternal life trough His blood.
12 In whom we have boldness and access with confidence by the faith of him.
Because of His sacrifice and because we believe in Him, we now have access to our Fathers throne. Through Christ we have direct way to God. You don't need to talk to anyone else. He hears you!
13 Wherefore I desire that ye faint not at my tribulations for you, which is your glory.
Those of you in Christ know full well the power you have been given. Your faith has grown and with it your strength.
14 For this cause I bow my knees unto the Father of our Lord Jesus Christ,
Thank our Father for sending us His Son, Christ Jesus Yahshua.
15 Of whom the whole family in heaven and earth is named,
Christians Family † "Family" = πατριά patriá, pat-ree-ah'; as if feminine of a derivative of G3962; paternal descent, i.e. (concretely) a group of families or a whole race (nation):—family, kindred, lineage. [A group of families, all those who in a given people lay claim to a common origin.] "Christian" = Χριστιανός Christianós, khris-tee-an-os'; from G5547; a Christian, i.e. follower of Christ:—Christian.
16 That he would grant you, according to the riches of his glory, to be strengthened with might by his Spirit in the inner man;
That inner person is your intellect, your soul. Your outwardly person has no real relevance to what that inner is. Some may find you ugly or beautiful, that's opinions, what is in you counts and is built on facts. Is Christ in you and therefore built on strength and power with confidence and eternal life, or is it full of the worldly and satans deceptions that bring death?
17 That Christ may dwell in your hearts by faith; that ye, being rooted and grounded in love,
If you believe in Him, He will live in you. The outcome is one that is able under any circumstances and ready to give of themselves when called for.
18 May be able to comprehend with all saints what is the breadth, and length, and depth, and height;
Love opens doors to all things. When you love The Lord, He will then open the doors.
19 And to know the love of Christ, which passeth knowledge, that ye might be filled with all the fulness of God.
20 Now unto him that is able to do exceeding abundantly above all that we ask or think, according to the power that worketh in us,
Only in Christ Jesus can you have true wealth. That wealth is the love He has for us in bringing us to The Truth. In The Truth is power. In that power is the ability to do His work.
21 Unto him be glory in the church by Christ Jesus throughout all ages, world without end. Amen.
The world will never end, this flesh age is about to. Are you ready? Have you asked Christ into your hearts? To Him, Christ Jesus is my glory, forever Amen. †