This below is an excerpt of “Foundations of Dispensational Truth” by the late Dr E.W. Bullinger.

This brings us to the third sphere, which is the greatest blessing of all, and the highest in glory.

It had been kept secret “from ages and from generations.” It is of the eternal “purpose” of God, made “before the foundation of the world,” and was not “made manifest” through the prophetic writings. 

It was a secret not relating to Israel on the earth; nor to the “partakers of a heavenly calling”; but to Christ and the elect members of “His body.”

Even in the ministry of Christ it was among the things He could not then reveal even to the twelve apostles in the privacy of the upper room after the last supper. Not only could He not say these things then, but the apostle themselves would not have been able to bare them if He had.

And, since the Lord did not mention these things during the time of the four Gospels, then certainly the apostles could not have “confirmed” them in the Acts of the Apostles, afterward.

They were “the things of Christ,” i.e., those things which stand in a special relation to Him, the things that relate to the whole of the truth, “the truth” which would not be complete without them.

They were, of necessity, reserved for “the Spirit of truth” to reveal. “HE will guide you into the whole of the truth.” (cf. John 16:13)

These precious “riches of grace,” and glory, these were the doctrines which had for their foundation the facts of Christ’s mission, which had not at that time taken place: though they were all then near at hand.

Those events in Christ’s life on earth were the foundation of the doctrines built upon them; and without them the doctrines could not have been known.

Until He had suffered, died. risen. and ascended, how could the doctrines of Eph. 2:5-6 based on them be revealed and taught. “Even when we were dead in sins, hath quickened us together with Christ, (by grace ye are saved;) ⁶ And hath raised us up together, and made us sit together in heavenly places in Christ Jesus:” (Ephesians 2:5-6 (KJV)

We must include that last phase of what “Jehovah hath spoken” before we commence our consideration of Paul’s Prison Epistles: for therein and only therein, do we find the “riches” of grace and glory into which the Holy Spirit was to guide: them, the good news of which was destined to fill the long era of Israel’s blindness and the nation’s dark (spiritual,) night (cf. Isa. 60:1-3).

Paul’s Prison Epistles (written post-Acts) immediately follow the proclamation of Israel’s judicial blindness and hardening (recorded in Acts 28: 25-26), have for their one great subject the revelation of the third of the three spheres of blessing and glory which stands in special relation to Christ and His “church. which is His body.”

• This sphere is not on the earth.
• It is not over the earth.
• It is in the “highest heavens.”

Hence, this truth has nothing to do with earthly “signs and wonders” (of the Acts period) that would follow those who in happy obedience believe what is written there.

Such surpassingly exalted language has never before or since been spoken of human believers. The very glory of that third sphere is inconsistent with any earthly signs or manifestations however wonderful. or, ordinances, however once significant. 

Those later Pauline Epistles view the believer of them, not with “signs following,” but they view the believer as “dead” to this world and all earthly associations and connections, and as having jointly suffered, jointly died, jointly risen, and being Jointly Seated With Christ In The Highest Heavens.

Even the “affections” and “thoughts” are not to be concerned with the things on earth; they are to be centered on “the things above” where Christ is already seated at the right hand of God.

Hence, we do not read in those Epistles about the coming of Christ to the earth, but rather about our being removed to be with Him where He is, not about His parousia, or presence on earth, or “in the air “; but about our presence and manifestation appearing with Him in His own glory; not about anastasis or resurrection (which is the subject of the earlier Pauline Epistles), but about an “ex-anastasis,” (Phil. 3: 11) and “the calling on high” (Phil. 3: 14) which is the subject of Paul’s later Epistles; not about any personal happiness which we may have, but about Christ’s personal glory, in which we have the wondrous privilege of sharing.

In this connection we would call attention to one word, which, in our judgment, is the real key-word of the Prison Epistles, and of this third and highest sphere. It is a remarkable word, found. in this form, only here, in the New Testament. It occurs once before in Rom. 13:9, but there it is in the present passive voice (anakephalaioutai), and means “is summed up.” But in Eph. 1:10 (below) it is the Aorist Infinitive of the middle voice, (anakephalaiosasthai).

“^9b … according to his good pleasure which he hath purposed in himself: ¹⁰ That in the dispensation of the fulness of times he might gather together in one all things in Christ, both which are in heaven, and which are on earth; even in him: ¹¹ In whom also we have obtained an inheritance, being predestinated according to the purpose of him who worketh all things after the counsel of his own will: Ephesians 1:9-11 (KJV)

This difference is ignored both by the KJ Authorized and the Revised Versions, which read the middle voice of Eph. 1. To as though it were the Active. This is an almost unpardonable oversight, in the interest of the ordinary Bible reader, who has an undoubted right to a correct grammatical rendering from such a quarter. Translated correctly, the word and the entire passage emphasize the underlying fact that in all things there revealed, our Heavenly Father has, FOR HIMSELF, purposed what is here stated;

… according to His good pleasure, which He purposed in Himself, in order to a dispensation of the fulness of the seasons, TO-SUM-UP-FOR-HIMSELF, everything in Christ: things in heaven and things on earth, even in Him, in whom we were taken as an inheritance, being foreordained according to the purpose of Him who worketh all things according to the counsel of His own will, that we should be to the praise of His glory who have before hoped in Christ. (Ephesians 1:10-11 corrected)

This will be enough to show us that the Cosmos, as shown in Col. 1: 15-16, is a larger, higher, and greater sphere than that of earthly glory, or (a) that of the glory reserved for those who are partakers of a heavenly calling.

The Old Testament and the earlier Pauline Acts Epistles deal with these two lower spheres of glory, but the later Epistles reveal a third sphere of Headship and Heirship above the earth or the (lower) heavens. 1 Cor. 15:40 tells of “terrestrial (earthly)” glory and of “celestial’s glory, which differ the one from the other.

But there is a third sphere; a sphere of cosmical glory (if we may use the word in this connection) high above all created beings, whether principalities, or powers, or, might, or thrones, or dominions, which are mentioned (though not defined or explained) in Eph. 1:21, Col. 1: 16 in relation to Christ, who shall be “Head over all.”

“Far above all principality, and power, and might, and dominion, and every name that is named, not only in this world, but also in that which is to come:” Ephesians 1:21 (KJV)
“For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: all things were created by him, and for him:” Colossians 1:16 (KJV)

This includes the putting down of all enemies, and the final crushing of the head of “the old serpent” the devil.

This is why the enemy’s great endeavour, now, is to blind the minds of men so that the light of this “good news (gospel) of the glory of Christ” should be hidden from them (2 Cor. 4:3-4).

And this is why we, who obey God by believing Him as to this, His greatest and most glorious revelation, should cherish it as our earnest hope and constant theme; and, not being “ignorant of Satan’s devices,” since we are thus told against what his assault is being made, therefore know where our defence is to be directed.

In other words, we are to labour to make known: the riches of glory which are connected with this third and Highest sphere of blessing and glory and honour for “Christ and His Church.”