literally, Far off is that which hath been i. e., events as they have occurred in the order of Divine Providence), and deep, deep, who can find it out?

That which is far off - Though the wisdom that is essential to our salvation may be soon learned, through the teaching of the Spirit of wisdom, yet in wisdom itself there are extents and depths which none can reach or fathom.

That which is far off, (r) and exceedingly deep, who can find it out?
(r) Meaning wisdom.

That which is far off,.... Or, "far off is that which has been" (g). That which has been done by God already, in creation and providence, is out of the reach of men, is far from their understandings wholly to comprehend or account for; and likewise that which is past with men, what has been done in former ages, the history of past times, is very difficult to come at: or rather, according to Schmidt, and Rambachius after him, what was of old is now afar off or absent; the image of God in man which consisted of perfect wisdom, and was created at the same time with him, is now lost, and that is the reason why wisdom is far from him;
and exceeding deep, who can find it out? the primitive perfect wisdom is sunk so deep and gone, that no man can find it to the perfection it was once enjoyed; see Job 28:12. This may respect the knowledge of God, and the perfections of his nature; which are as high as heaven, and deeper than hell, Job 11:7; and of his thoughts, counsels, purposes, and decrees, which are the deep things of God; as well as the doctrines of the Gospel, and the mysteries of grace, 1-Corinthians 2:10; and even his providential dispensations towards the sons of men, Romans 11:33. The Targum of the whole is,
"Lo, now it is far off from the children of men to know all that has been from the days of old; and the secret of the day of death, and the secret of the day in which the King Messiah shall come, who is he that shall find it out by his wisdom?''
(g) "remotum (est) illud quod fuit", Montanus, Mercerus, Vatablus, Drusius, Gejerus.

That . . . far off . . . deep--True wisdom is so when sought independently of "fear of God" (Ecclesiastes 7:18; Deuteronomy 30:12-13; Job 11:7-8; Job 28:12-20, Job 28:28; Psalm 64:6; Romans 10:6-7).

"For that which is, is far off, and deep, - yes, deep; who can reach it?" Knobel, Hitz., Vaih., and Bullock translate: for what is remote and deep, deep, who can find it? i.e., investigate it; but mah-shehayah is everywhere an idea by itself, and means either id quod fuit, or id quod exstitit, Ecclesiastes 1:9; Ecclesiastes 3:15; Ecclesiastes 6:10; in the former sense it is the contrast of mah-shěihyěh, Ecclesiastes 8:7; Ecclesiastes 10:14, cf. Ecclesiastes 3:22; in the latter, it is the contrast of that which does not exist, because it has not come into existence. In this way it is also not to be translated: For it is far off what it (wisdom) is (Zckl.) [= what wisdom is lies far off from human knowledge], or: what it is (the essence of wisdom), is far off (Elst.) - which would be expressed by the words מה־שּׁהיא. And if מה־שׁהיה is an idea complete in itself, it is evidently not that which is past that is meant (thus e.g., Rosenm. quod ante aderat), for that is a limitation of the obj. of knowledge, which is unsuitable here, but that which has come into existence. Rightly, Hengst.: that which has being, for wisdom is τῶν ὄντων γνῶσις ἀψευδής, Wisd. 7:17. He compares Judges 3:11, "the work which God does," and Ecclesiastes 8:17, "the work which is done under the sun." What Koheleth there says of the totality of the historical, he here says of the world of things: this (in its essence and its grounds) remains far off from man; it is for him, and also in itself and for all creatures, far too deep (עמק עמק, the ancient expression for the superlative): Who can intelligibly reach (ימץ, from מצא, assequi, in an intellectual sense, as at Ecclesiastes 3:11; Ecclesiastes 8:17; cf. Job 11:7) it (this all of being)? The author appears in the book as a teacher of wisdom, and emphatically here makes confession of the limitation of his wisdom; for the consciousness of this limitation comes over him in the midst of his teaching.

It - God's counsels and works, and the reasons of them.