Rashi on Exodus 14:12/רש"י על שמות י״ד:י״ב

1אשר דברנו אליך במצרים [THE WORD] THAT WE SPOKE UNTO THEE IN EGYPT — And where had they said this? (Exodus 5:21) “The Lord look upon you and judge!” (Mekhilta)

2ממתנו means THAN THAT WE SHOULD DIE. If the word had been punctuated with a Melopum (our חולם i. e. מִמּוֹתֵנוּ) it would have to be explained “than our death” (מוֹתֵנוּ our death from the noun מָוֶת) but now that it is punctuated with a שורק (our Kibbutz) it must be explained by “than that we should die”. And similar is, (Exodus 16:3) “Would that מוּתֵנוּ” i. e. “that we should die”; similar is, (II Samuel 19:1) “Would that מוּתִי” in the history of Absalom, which means “that I should die”. It is an infinitive like (Zephaniah 3:8) “Until the day קוּמִי for ever”, and as (II Chronicles 18:26) “Until the day שׁוּבִי in peace” — which signify שאקום “that I shall arise”, and שאשוב “that I shall return”.