Get wisdom - True religion is essential to thy happiness; never forget its teachings, nor go aside from the path it prescribes.

Get wisdom, get understanding,.... Not only moral and political wisdom and understanding, but that which is spiritual and evangelical; Christ, and the knowledge of him; he being the only happy man that has an interest in him, and is possessed of him by faith, which is the meaning of getting him; See Gill on Proverbs 3:13; by which it appears, that what Solomon had before delivered, and afterwards repeats and urges, was the same his father David, that wise, great, and good man, taught him; and which he mentions, the more to recommend the getting of wisdom and understanding to others;
forget it not; when gotten, keep it in remembrance; be continually meditating on Wisdom, or Christ, his glories and excellencies; the fulness of grace and truth in him; the blessings of goodness which come by him; the great use and profit of having and enjoying him;
neither decline from the words of my mouth; the above instructions, and all others he gave unto him.

Get--as a possession not to be given up.
neither decline--that is, from obeying my word.

The exhortation of the father now specializes itself:
5 Get wisdom, get understanding;
Forget not and turn not from the words of my mouth.
6 Forsake her not, so shall she preserve thee;
Love her, so shall she keep thee.
Wisdom and understanding are (5a) thought of as objects of merchandise (cf. Proverbs 23:23; Proverbs 3:14), like the one pearl of great price, Matthew 13:46, and the words of fatherly instruction (5b), accordingly, as offering this precious possession, or helping to the acquisition of it. One cannot indeed say correctly אל־תשׁכח מאמרי־פי, but אל־תשׁכח משּׁמר אמרי־פי (Psalm 102:5); and in this sense אל־תּשׁכּח goes before, or also the accus. object, which in אל־תשכח the author has in his mind, may, since he continues with אל־תּט, now not any longer find expression as such. That the אמרי־פי are the means of acquiring wisdom is shown in Proverbs 4:6, where this continues to be the primary idea. The verse, consisting of only four words, ought to be divided by Mugrash;
(Note: According to correct readings in codd. and older editions, ותשמרךּ has also indeed Rebia Mugrash, and אהבה, Mercha (with Zinnorith); vid., Torath Emeth, p. 47, 6; Accentuationssystem, xviii. 1, 2; and regarding the Zinnorith, see Liber Psalmorum Hebraicus by S. Baer, p. xii.)
the Vav (ו) in both halves of the verse introduces the apodosis imperativi (cf. e.g., Proverbs 3:9., and the apodosis prohibitivi, Proverbs 3:21.). The actual representation of wisdom, Proverbs 4:5, becomes in Proverbs 4:6 personal.