People say, “We do not laugh because we are happy; we are happy because we laugh.” The point of the saying is the state of the mind of the person is significant for happiness. It is implied that, if the person has something in mind concerning about, it keeps him or her from laughing. In this regard, laughing is an metonymy of the evidences of the state of mind in which there is nothing that prevents the person from joy. But it does not explain that laughter can make the person happy which the saying means.
This why laughter makes the person happy. Laughing is not only an expression of the happiness that is already in the heart of the person, but it is also an endeavor of the person in fighting against the negative things that may be or attempt to come into the heart. However, the effort does not necessarily clear up the mind of the negative things that he or she can laugh. What makes the person be able the laugh, therefore, is the person’s attitude of endeavoring to overcome those hindering things. It is by looking to hope over the negative things that are around him or her. It is possible, so, by faith and trust in the Being who gives him or her the hope and the spiritual strength to live such. For this reason, laughter is the evidence of faith and hope as well as of the effort of the person.
This is the idea that the scripture teaches: “May the God of hope fill you with all joy and peace as you trust in him, so that you may overflow with hope by the power of the Holy Spirit” (Romans 15:13; ESV; emphasis mine). So that we may have joy and peace, we need to be filled with hope; and the hope is by faith in Him who is the “God of hope.”