More on Old Hundredth from Infoplease:

• doxology - doxology doxology [Gr. doxa=glory] formulaic ascription of praise to God, encountered in Jewish, ...
• Encyclopedia: Roman Catholic and Orthodox churches: Liturgy, Hymns, and Prayers - Encyclopeadia articles concerning Roman Catholic and Orthodox churches: Liturgy, Hymns, and Prayers.
• hymn - hymn hymn, song of praise, devotion, or thanksgiving, especially of a religious character (see also ...
• Hurrah' - Hurrah' the Hebrew . Our “Old Hundredth Psalm” begins with “Shout joyfully ...

See more Encyclopedia articles on: Roman Catholic and Orthodox churches: Liturgy, Hymns, and Prayers