When I think of God, my heart is so full of joy that the notes leap and dance as they leave my pen; and since God has given me a cheerful heart, I serve Him with a cheerful spirit.

From Proverbs 15:15:  All the days of the poor are hard, but a cheerful heart has a continual feast.”

Franz Joseph Haydn (1732-1809) was an Austrian composer.  Some of his most instrumental achievements dealt with the development of chamber music (both string quartet and piano trio).