It is very clear that the Buddha wants us to be nourished by our joy and happiness. Without joy and happiness, we can not go very far as a practitioner. And that is why each practitioner of Buddhism should be able to generate the energy of joy, to generate the energy of happiness at a time s/he wants to. And we ask the question, how to do that, how to bring in the moment of joy, how to bring in a feeling of happiness.
And the teaching of Buddha on this matter is very clear. There are many ways to bring in a feeling of joy. There are many ways to bring in a feeling of happiness. And the first method known to everybody is to let go. If you know how to let go, a feeling of joy may come, a feeling of happiness may come. And the question is "let go of what?". There are many things we should let go. And we have to consider them during our sitting meditation.
This expression (離生喜楽) is known to every Buddhist. Joy and happiness can be born from the practice of letting go. There are things that we should be able to let go if we want to have joy and happiness.
Suppose you live in a very big city, very crowded city and you smell a lot of unpleasant smells and you hear a lot of noise. And you suffer and you would like to get out of the city and to go to the countryside in order to stop that kind of suffering. When you live in a city like Tokyo, New York, Los Angels, you suffer because of the situation in the big cities. And one day you decide to leave the city for a weekend. You have to make many kinds of arrangements so that you can upcharge during the weekend. It's not easy. And when you are ready, you get into your car and you drive out of the city. And it needs at least one hour for you to get out of the big city like Los Angels. And after that, you begin to see Rolling Hills, beautiful trees, the moon, the flowers and you can hear the birds singing. You feel you are very happy, you are free because you are able to leave the city behind. That is the joy and happiness born from leaving, releasing behind, letting go.
Suppose you have an idea that you can not release. Very often, joy is not possible, happiness is not possible because you always entertain that idea. You have an idea of happiness. You think that you can be only happy when you can obtain that or you can get rid of that. And you spend all your time trying to get it or to get rid of it. And during that time, joy and happiness is not possible. You believe that without that diploma, the position, that person, it is impossible to be happy. You may think that if you can not obtain that person, the situation, that will be impossible for you to be happy. And what makes you unhappy now is not the city but the idea that you entertain in your head. If you know how to let go of your idea, joy and happiness will naturally come.
You need some courage in order to let go of that idea. You need some wisdom, some insight (regarding the nature of idea) in order to be strong enough to let go of that idea. Every one of us entertains the idea about happiness and maybe if you are not happy, just because you have not been able to get rid of that idea of happiness.