The Holy Ghost - Who appointed all this. The whole arrangement in the service of the tabernacle is represented as having been under the direction of the Holy Spirit, or this was one of his methods of teaching the great truths of religion, and of keeping them before the minds of people. Sometimes that Spirit taught by direct revelation; sometimes by the written word, and sometimes by symbols. The tabernacle, with its different apartments, utensils, and services, was a permanent means of keeping important truths before the minds of the ancient people of God.
This signifying - That is, showing this truth, or making use of this arrangement to impress this truth on the minds of people that the way into the holiest of all was not yet made manifest.
That the way into the holiest of all - Into heaven - of which the Most Holy place in the tabernacle was undoubtedly designed to be an emblem. It was the place where the visible symbol of God - the Shekinah - dwelt; where the blood of propitiation was sprinkled, and was, therefore, an appropriate emblem of that holy heaven where God dwells, and whence pardon is obtained by the blood of the atonement.
Was not yet made manifest - The way to heaven was not opened or fully understood. It was not known how people could appear before God, or how they could come with the hope of pardon. That way has now been opened by the ascension of the Redeemer to heaven, and by the assurance that all who will may come in his name.
While as the first tabernacle was yet standing - As long as it stood, and the appointed services were held in it. The idea is, that until it was superseded by a more perfect system, it was a "proof" that the way to heaven was not yet fully and freely optioned, and that the Holy Spirit "designed" that it should be such a proof. The apostle does not specify in what the proof consisted, but it may have been in something like the following.
(1) it was a mere "symbol," and not the "reality" - showing that the true way was not yet fully understood.
(2) it was entered but once a year - showing that there was not access at all times.
(3) it was entered only by the High Priest - showing that there was not free end full access to all the people.
(4) it was accessible only by Jews - showing that the way in which all men might be saved was not then fully revealed.
The sense is, that it was a system of types and shadows, in which there were many burdensome rites and many things to prevent people from coming before the symbol of the divinity, and was, therefore, an "imperfect system." All these obstructions are now removed; the Saviour - the great High Priest of his people - has entered heaven and "opened it to all true believers," and all of every nation may now have free access to God; see Hebrews 9:12; compare Hebrews 10:19-22.

The Holy Ghost this signifying - These services were divinely appointed, and by each of them the Holy Spirit of God is supposed to speak.
The way into the holiest - That full access to God was not the common privilege of the people, while the Mosaic economy subsisted. That the apostle means that it is only by Christ that any man and every man can approach God, is evident from Hebrews 10:19-22, and it is about this, and not about the tabernacle of this world, that he is here discoursing.
I have already observed that the apostle appears to use the word σκηνη, or tabernacle, in the general sense of a dwelling place; and therefore applies it to the temple, which was reputed the house or dwelling place of God, as well as the ancient tabernacle. Therefore, what he speaks here concerning the first tabernacle, may be understood as applying with propriety to the then Jewish temple, as well as to the ancient tabernacle, which, even with all their sacrifices and ceremonies, could not make the way of holiness plain, nor the way to God's favor possible.

(3) The Holy Ghost this signifying, that the way into the holiest of all was not yet made manifest, while as the first tabernacle was yet standing:
(3) Of that yearly rite and the ceremony, he gathers that the way into heaven was not opened by such sacrifices, which was shadowed by the Holiest of all. For why did only the high priest enter in, excluding all others, to offer sacrifices there both for himself and for others, and after, shut the Holiest of all again?

The Holy Ghost this signifying,.... This shows that the Holy Ghost existed under the Old Testament; that he is a distinct person in the Godhead, a personal act being here ascribed to him; that he is truly and properly God, the God whose service the priests accomplished in the tabernacle; and by whom Moses was admonished to make all things in it according to the pattern, and by whom the high priest was warned not to come at all times within the vail; moreover, that the Levitical ordinances were of God, and that they had a spiritual signification; that the Old Testament saints were not without some knowledge of the spiritual meaning of them; and that the Holy Ghost was the author of that knowledge; particularly by enjoining the high priest to enter within the vail but once a year, he gave a plain and strong intimation,
that the way into the holiest of all was not yet manifest, while as the first tabernacle was yet standing; by which is meant, not only the first part of the tabernacle, as in Hebrews 9:2 but the whole of it; and not only that, but the temple built in its room, and also the whole Levitical service is included; and the sense is, that while the tabernacle and tabernacle worship, the temple and temple service, were in being, "the way into the holiest of all was not yet manifest": the Vulgate Latin and all the Oriental versions render it, "the way of the saints"; of the priests who ministered in holy things, and were holy to the Lord, and of all the saints that lived before Christ; not that they did not go to heaven, but their way to it was not so manifestly known; life and immortality were not so clearly brought to light, as now by the Gospel; though rather it designs holy places, even heaven itself, which was typified by the holy place within the vail; and may be called the holiest of all, it being the residence of the holy God, holy angels, and holy men, and is sanctified by the presence of Christ, for his people, and where perfect holiness will be the glory of it: the way to it is not by works of righteousness done by men, which being imperfect cannot justify, and so not save, though this is the way men naturally seek and take; but Christ is the only way, and he is the plain, pleasant, and safe one: now let it be observed, that heaven was not shut to the Old Testament saints; there was a way into it for them, and they went the same way New Testament saints do; and that way was in some measure known, but it was not fully manifested; it lay hid in obscure prophecies, types, shadows, and sacrifices; hence being more clearly revealed under the Gospel dispensation, in comparison, of its former obscurity, and with respect to the manifestation of it, it is called a "new way".

The Holy Ghost--Moses himself did not comprehend the typical meaning (1-Peter 1:11-12).
signifying--by the typical exclusion of all from the holiest, save the high priest once a year.
the holiest of all--heaven, the antitype.
the first tabernacle--the anterior tabernacle, representative of the whole Levitical system. While it (the first tabernacle, and that which represents the Levitical system) as yet "has a standing" (so the Greek, that is, "has continuance": "lasts"), the way to heaven (the antitypical "holiest place") is not yet made manifest (compare Hebrews 10:19-20). The Old Testament economy is represented by the holy place, the New Testament economy by the Holy of Holies. Redemption, by Christ, has opened the Holy of Holies (access to heaven by faith now, Hebrews 4:16; Hebrews 7:19, Hebrews 7:25; Hebrews 10:19, Hebrews 10:22; by sight hereafter, Isaiah 33:24; Revelation 11:19; Revelation 21:2-3) to all mankind. The Greek for "not yet" (me po) refers to the mind of the Spirit: the Spirit intimating that men should not think the way was yet opened [TITTMANN]. The Greek negative, "ou po," would deny the fact objectively; "me po" denies the thing subjectively.

The Holy Ghost evidently showing - By this token. That the way into the holiest - Into heaven. Was not made manifest - Not so clearly revealed. While the first tabernacle, and its service, were still subsisting - And remaining in force.