A glad heart makes a cheerful face, but by the sorrow of heart the spirit is crushed. Proverbs 5:13
And I command joy, for man has no good thing under the sun but to eat and drink and be joyful, for this will go with him in his toil through the days of his life that God has given him under the sun. Ecc. 8:15
God wants us to celebrate. There are so many examples in scripture about being joyful. God requires us to have fun while we are able.