Until I went into the sanctuary of God - The word “sanctuary” we now apply to a place of public worship; and, thus understood, the passage here would mean that he learned the truth on the subject only by the statements and disclosures made there in regard to the divine plans and dealings, and the results of human conduct. This interpretation makes good sense, and is in itself true, but it is not the idea in the original. The word “sanctuary” in the Old Testament, in the singular number, is applied to the tabernacle, or the temple, or, more especially to the most holy place in the tabernacle or the temple; the place of the unique dwelling of God. Thus understood the idea would be that he learned the solution of the mystery “there.” But these were not places of instruction, and it cannot be supposed that the reference is to either of them. The word in the original is in the plural number - sanctuaries - things that God regarded as holy; and the meaning seems to be, that the only solution of the case was to be learned from those things which pertained to God’s most holy and secret places; or in those places which were nearest to him, and where he most clearly manifested himself. The difficulty was not to be solved by any mere human reasoning - by the powers of man, away from God; it was to be learned in the presence of God himself, and in the disclosures which He made about his divine plans and purposes. The psalmist had tried his own powers of reason, and the subject was above his reach. The only solution of the difficulty was to be obtained by a near approach to God himself. There the mystery could be solved, and there it was solved. The “end” of all this, as disclosed by God, would determine why, it was permitted, and would remove the perplexity of the mind.
Then understood I their end - literally, their after things; that is, the things which will occur to them hereafter. That solves all the difficulty. There will be a judgment hereafter, and dark as things may now appear, it will be seen in the end, or in the result, that exact and equal justice will be done to all.