So I hated all the fruit (gain) of my labor for which I had labored under the sun, because I must leave it to the man who will succeed me.

If the axe is dull and he does not sharpen its edge, then he must exert more strength; but wisdom [to sharpen the axe] helps him succeed [with less effort].

If the snake bites before the charming, {the snake charmer will not succeed}.

Sow your seed in the morning, and do not let your hands rest in the evening, for you do not know what will prosper-- whether this or that, or whether both of them alike will succeed.