I recently attended a Mass and the priest forgot to give the Final Blessing. Did this make the mass illicit (as I understand, the terms licit and illicit are used instead of valid and invalid)?
Licit does not mean valid. Valid means that something is what it is supposed to be in its essentials. Licit only means legal or according to the law. If some unessential element of the Mass or a sacrament is missing, it is still valid, but illicit. The Mass you mention was valid, but the priests forgetting to the give the blessing is illicit. Liturgical law requires that the blessing be given.
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