Dicit dominus implete idrias aqua et
Text variant "dum gustasset".
Imperfect plagal mode of Gsolreut. The modal diathesaron is not reached (only a semiditonus).
Some other sources show plagal mode of Ffaut; which in melodic terms is the same: mode of ut. The second below the finalis in G mode could also be a semitonus (fa diesis at "ihesus primum") in order to avoid the tritonus Bmi-Ffa.