Musar for Exodus 34:28

[And this is the intent of Mishlei 4:7: "The beginning of wisdom is to acquire wisdom," and, the end of the verse: "and with all of your acquisitions, acquire understanding." This is self-explanatory: "Wisdom" connotes what is apparent, first principles, what one learns from others; and "understanding," what one reflects upon thereafter by himself, to understand one thing from another. Therefore, he says that first one must acquire wisdom, and then he must strengthen himself to understand one thing from another. As they said (Shabbath 31a): "At the time of judgment they ask a man: 'Did you discourse in wisdom? Did you understand one thing from another?''' As to "and with all your acquisitions, acquire understanding," this is understood according to Midrash Shir Hashirim 8 in the episode of R. Chiyya b. Abba and R. Yochanan, who were walking on the way and came upon a field, at which R. Yochanan said: "This was mine, but I sold it to toil in Torah," and thus, until the last field. At this, R. Chiyya began to cry, and said to him: "What will you leave over for your old age?" R. Yochanan answered: "Why does this disturb you? I sold something that was created in six days, as it is written (Shemoth 20:11): 'For six days the L-rd made, etc.', and I bought something which was learned in forty days, as it is written (Ibid. 39:28): 'And he was there with the L-rd for forty days.'" And this is what Scripture intimates to us in "and with all of your acquisitions acquire understanding." It is right that one give all he possesses to acquire understanding. That is, that he grow wise in all matters of Torah in order to understand one thing from another.]