In plain words
We do not see them, yet they feed us the fruits of many karmas. So this is the education we must learn today. To develop good thoughts. Whatever the thoughts may be, such are the results we go on reaping.
You sow seeds that give poison, you hope today for the most delicious fruits; unable to eat the very bitter fruits that grow, you push the blame onto Him and argue.
What you sow is poison seeds; what you hope for is sweet fruits. Unable to eat the bitter fruits that grow: blaming God for giving bitter fruits like these. These are not God's gift. You grew them yourself. So sow good seeds. Gain good fruits. In the same way I have spoken many times about the effects of thoughts. There are five crores of thoughts.
Only when we recognise well the effect of these thoughts can we fully recognise how precious our humanness is. If you truly understand well the chief secret in man, you can fully experience how precious humanness is, the truth "Jantūnāṃ narajanma durlabham." There is one quality in man that is in no other living being. If you ask what that quality is: laughing. No animals, no birds, no beasts laugh. That means that man is full of Ānanda. Since he longs for Ānanda, they said that man thirsts for Ānanda. Put a question mark to yourselves: why should man, so full of Ānanda, experience sorrow? That is, we weep precisely because we do things contrary to laughter. Whatever deed we do, we must do it as a deed of laughter. Among these laughs there are three kinds of laughter. One is laughing merely in jest. Another is laughing in a kind of disgust. That is, when certain fruits in our life do not come to us, when we feel a little disappointed, this laugh goes off in irritation: "(Chī...)" Another kind of laugh is laughing very loudly at everything, small and big, at what is no joke and at what is a joke. This is bad. We must not laugh in this way. They said we must not laugh with a noise, or with the lips drawn back so that the teeth show, or with the mouth flung open.