Mitzvos in Parshas Shelach

I want to try some new things in this blog. I like looking at Sefer HaChinuch, which discusses the 613 mitzvos as they occur in each weekly Torah-reading. Lists and summaries and things like that appeal to me, and I feel that knowing the mitzvos in each parshah is way of boiling it down to its essence. This week's parshah has three mitzvos from the 613 mitzvos (as enumerated by Maimonides), two positive and one negative. The positives: Taking challah, and wearing tzitzis. The negative, as the Sefer HaChinuch puts it, "not to go straying after one's heart and eyes." That seems to need a little explanation. The "heart" part seems to be entertaining thoughts that might lead to meenus--heresy, let's say. The "eyes" part has to do with entertaining physical desires for things forbidden by the Torah. That was easy, right? Just wait. Some parshas have a great many more mitzvos.