1) Closing musical selection 2) Closing piece of music 3) Musical afterthought 1) Epilog 
closing piece of music at end of church service
• (n.) A voluntary at the end of a service.
Post'lude noun [ Prefix post- + -lude , as in prelude .] (Medicine) A voluntary at the end of a service. 
postlude 1. In music, a concluding piece or movement played at the end of an oratorio or the like; a concluding voluntary. 2. A written or spoken epilogue; an afterword, a conclusion.
noun a voluntary played at the end of a religious service