Ecclesiastes - Chapter 11
Bread Upon the Waters
In a famous verse, King Solomon says, "Cast your bread upon the waters, for you will find it after many days." The meaning of this is that we should do acts of kindness for other people without the expectation of being repaid. Ultimately, others will "pay it forward" and do good things for us. Even if you've done kindness for seven people, don't think it's enough and you can stop. Do it for the eighth person as well because one never knows what kind of help he himself may need in the future.
Clouds that are full of rain will ultimately shower upon the Earth, and people will settle in a place where fruit trees grow. (The tree is also a metaphor for a Torah scholar.) Someone who waits for the wind will not plant, because the winds will scatter his seeds. Someone who is worried that it will rain will never harvest, because he'll always be afraid. Just like one cannot definitively know the weather before it happens, and one cannot know a baby before it's born, one cannot really hope to understand all of G-d's ways.
Plant your seeds in the morning and continue to do so in the afternoon, because you have no way of knowing which will take. (Rashi explains that we should learn Torah, do good deeds and raise students both in our youth and in our old age because we never know which ones will be more effective.) The light of Torah is pleasing and beneficial; those who see it are fortunate to be alive. If a person lives a good, long life, he should be happy with his lot. He should remember where we all end up and take advantage of his time to improve his deeds. To do otherwise would be to squander his afterlife - this would be supremely ridiculous! One should take advantage of his youth while he can, enjoying it while also knowing that G-d is keeping an eye on our actions. Get rid of things that anger Him and overcome your baser urges because physical pleasures are fleeting and insignificant.