Hebrews 9:8

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 Hebrews 9:6 ) 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".