A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
exo 40:2THE TABERNACLE REARED AND ANOINTED. (Exo. 40:1-38)
On the first day of the first month--From a careful consideration of the incidents recorded to have happened after the exodus (Exo 12:2; Exo 13:4; Exo 19:1; Exo 20:18; Exo 34:28, &c.), it has been computed that the work of the tabernacle was commenced within six months after that emigration; and consequently, that other six months had been occupied in building it. So long a period spent in preparing the materials of a movable pavilion, it would be difficult to understand, were it not for what we are told of the vast dimensions of the tabernacle, as well as the immense variety of curious and elaborate workmanship which its different articles of furniture required.
the tabernacle--the entire edifice.
the tent--the covering that surmounted it (Exo 40:19).
exo 40:15anoint them, as thou didst anoint their fathers--The sacred oil was used, but it does not appear that the ceremony was performed exactly in the same manner; for although the anointing oil was sprinkled over the garments both of Aaron and his sons (Exo 29:21; Lev 8:30), it was not poured over the heads of the latter. This distinction was reserved for the high priest (Exo 29:7; Lev 8:12; Psa 133:2).
exo 40:16Thus did Moses: according to all that the Lord commanded him--On his part, the same scrupulous fidelity was shown in conforming to the "pattern" in the disposition of the furniture, as had been displayed by the workmen in the erection of the edifice.
exo 40:33So Moses finished the work--Though it is not expressly recorded in this passage, yet, from what took place on all similar occasions, there is reason to believe that on the inauguration day the people were summoned from their tents--were all drawn up as a vast assemblage, yet in calm and orderly arrangement, around the newly erected tabernacle.
exo 40:34a cloud--literally, "The cloud," the mystic cloud which was the well-known symbol of the Divine Presence. After remaining at a great distance from them on the summit of the mount, it appeared to be in motion; and if many among them had a secret misgiving about the issue, how the fainting heart would revive, the interest of the moment intensely increase, and the tide of joy swell in every bosom, when that symbolic cloud was seen slowly and majestically descending towards the plain below and covering the tabernacle. The entire and universal concealment of the tabernacle within the folds of an impervious cloud was not without a deep and instructive meaning; it was a protection to the sacred edifice from the burning heats of the Arabian climate; it was a token of the Divine Presence; and it was also an emblem of the Mosaic dispensation, which, though it was a revelation from heaven, yet left many things hid in obscurity; for it was a dark cloud compared with the bright cloud, which betokened the clearer and fuller discoveries of the divine character and glory in the gospel (Mat 17:5).
the glory of the Lord filled the tabernacle--that is, light and fire, a created splendor, which was the peculiar symbol of God (Jo1 1:5). Whether this light was inherent in the cloud or not, it emanated from it on this occasion, and making its entry, not with the speed of a lightning flash as if it were merely an electric spark, but in majestic splendor, it passed through the outer porch into the interior of the most holy place (Kg1 8:10; Joh 1:14). Its miraculous character is shown by the fact, that, though "it filled the tabernacle," not a curtain or any article of furniture was so much as singed.
exo 40:35Moses was not able to enter into the tent of the congregation--How does this circumstance show the incapacity of man, in his present state, to look upon the unveiled perfections of the Godhead! Moses could not endure the unclouded effulgence, nor the sublimest of the prophets (Isa 6:5). But what neither Moses nor the most eminent of God's messengers to the ancient church through the weakness of nature could endure, we can all now do by an exercise of faith; looking unto Jesus, who reflected with chastened radiance the brightness of the Father's glory; and who, having as the Forerunner for us, entered within the veil, has invited us to come boldly to the mercy seat. While Moses was compelled, through the influence of overwhelming awe, to stand aloof and could not enter the tabernacle, Christ entered into the holy place not made with hands; nay, He is Himself the true tabernacle, filled with the glory of God, ever with the grace and truth which the Shekinah typified. What great reason we have to thank God for Jesus Christ, who, while He Himself was the brightness of the Father's glory, yet exhibited that glory in so mild and attractive a manner, as to allure us to draw near with confidence and love into the Divine Presence!
exo 40:36when the cloud was taken up from over the tabernacle--In journeying through the sandy, trackless deserts of the East, the use of torches, exhibiting a cloud of smoke by day and of fire by night, has been resorted to from time immemorial. The armies of Darius and Alexander were conducted on their marches in this manner [FABER]. The Arab caravans in the present day observe the same custom; and materials for these torches are stored up among other necessary preparations for a journey. Live fuel, hoisted in chafing dishes at the end of long poles, and being seen at a great distance, serves, by the smoke in the daytime and the light at night, as a better signal for march than the sound of a trumpet, which is not heard at the extremities of a large camp [LABORDE]. This usage, and the miracle related by Moses, mutually illustrate each other. The usage leads us to think that the miracle was necessary, and worthy of God to perform; and, on the other hand, the miracle of the cloudy pillar, affording double benefit of shade by day and light at night, implies not only that the usage was not unknown to the Hebrews, but supplied all the wants which they felt in common with other travellers through those dreary regions [FABER, HESS, GRANDPIERRE]. But its peculiar appearance, unvarying character, and regular movements, distinguished it from all the common atmospheric phenomena. It was an invaluable boon to the Israelites, and being recognized by all classes among that people as the symbol of the Divine Presence, it guided their journeys and regulated their encampments (compare Psa 29:1-11; Psa. 105:1-45).
exo 40:38the cloud of the Lord was upon the tabernacle, &c.--While it had hitherto appeared sometimes in one place, sometimes in another, it was now found on the tabernacle only; so that from the moment that sanctuary was erected, and the glory of the Lord had filled the sacred edifice, the Israelites had to look to the place which God had chosen to put His name there, in order that they might enjoy the benefit of a heavenly Guide (Num 9:15-23). In like manner, the church had divine revelation for its guide from the first--long before the WORD of God existed in a written form; but ever since the setting up of that sacred canon, it rests on that as its tabernacle and there only is it to be found. It accompanies us wherever we are or go, just as the cloud led the way of the Israelites. It is always accessible and can be carried in our pockets when we walk abroad; it may be engraved on the inner tablets of our memories and our hearts; and so true, faithful, and complete a guide is it, that there is not a scene of duty or of trial through which we may be called to pass in the world, but it furnishes a clear, a safe, and unerring direction (Col 3:16).