This Easter song from RS’s parish is to the tune LASST UNS ERFREUEN with extra Alleluias! The text is listed as from “Compilers” 1978 and can be found here. (scroll down)
The music is listed as from Auserlesene Catholische Geistliche Kirchengesänge, 1623. Sheet music can be purchased at OCP.
The tune I have blogged elsewhere but this one has extra alleluias so I’ve done a new backing.