% !TEX TS-program = LuaLaTeX+se
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\usepackage[autocompile]{gregoriotex}
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\begin{document}

\def\mysnippet{
    \gabcsnippet{
    (c4)() <sp>V/</sp>.[<sp>V/</sp>.]() In[In the name of the Father, ~~and of the Son,](g)
    no(h)mi(h)ne(h) Pa(h)tris,(g) et(h) () Fi(i)li(h)i,(h_') (,)
    et(h) Spi(h)ri(g)tus(h) Sanc(hg)ti.(g.) (::)
    <sp>R/</sp>.[<sp>R/</sp>.]() <b>A</b>[Amen.](g)<b>men.</b>(gh..) (:: )
    }
}

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\mysnippet

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\gresetinitiallines{zork}
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