Variantly: You will be plowing in the time of harvesting, and harvesting in the time of plowing, as Iyyov said (Iyyov 29:19) "and the dew rested on my harvest."
Variantly: "and you shall gather in your corn": Why is this written" (i.e., Is it not obvious?) Because it is written (Joshua 1:8) "Let not this book of the Torah depart from your mouth," I might think this was to be taken literally (i.e., that one must never leave off learning); it is, therefore, written "and you shall gather in your corn" — follow the way of the land (i.e., Engage in an occupation and learn when not thus engaged.) These are the words of R. Yishmael. R. Shimon b. Yochai says: If a man harvests in harvest time and plows in plowing time and threshes in threshing time and winnows when there is wind, when will he learn Torah? But, when Israel does the L-rd's will its work is done by others, as it is written (Isaiah 61:5) "And strangers shall arise and graze your flocks"; and when they do not do the L-rd's will, they must do their own work. And, what is more, the work of others is done by them, as it is written (Devarim 28:48) "And you shall serve your foes."