Do you think that the flame on the candle is going down only in a vertical direction? If you think so, then you are following the flame in time. You may also think in this way about your own life span: that it is going in a linear direction and that one day it will end. You may think that you were born on a point on a vertical line, a point you may call 1960. You may think that you will die on a point somewhere farther down on that line, which you may call 2040. All you can see is yourself moving in time like the candle. But you are not just moving in a linear direction.
You might think that the flame is just going down. You might think that the candle will die. In fact the flame is going out in many other directions. It is giving out light all around itself to the north, south, east and west. If you had a very sensitive scientific instrument, you would be able to measure the heat and light that the candle is sending out into the universe. The candle is going into you as an image, as light and as heat.
You are like a candle. Imagine you are sending light out around you. All your words, thoughts and actions are going in many directions. If you say something kind, your kind words go in many directions, and you yourself go with them. We are transforming and continuing in a different form at every moment.
— Thich Nhat Hanh – No Death, No Fear – Pages 121 and 122
This text is illustrated by this example following the text above on page 122:
This morning you said something unkind to your child. With those unkind words you went into her heart. Now you are regretting what you said. It does not mean that you cannot transform what you have said by admitting your mistake to your child, but if you fail to do so, those unkind words may stay with your child for a long time.