Remembering that the Book of Proverbs is a book of parables, Solomon returns to the illustration of the son being instructed by his father. The father gives instructions and if those instructions are despised, then if the father is carried away by sudden illness and death, or dies naturally, the son would not be able to take over the family business and run the smallholding.
My son, keep my words - guard them, don't let them be stolen away from you. Lay up my commandments with thee, as though they were treasure. The illustration is of somebody who has plenty and gets great comfort and a sense of security at the thought that he has all this stored up or banked somewhere. Well, many of the illustrations in Proverbs are not themselves to be aimed at but what they illustrate is important. That is what you have to be like with the word of God, with truth. This is what should be your pleasure. This is what you should value and put your security in.