1Co1Cor 1 Corinthians1 Corinzi, chaptercapitolo First Epistle to the CorinthiansPrima Lettera ai Corinzi, chaptercapitolo 5

Purge out therefore the old leaven, that you2f may be a new lump, as you2f are unleavened. For even Moshiach [Messiah] our Passover is sacrificed for us:Isa 53:7

Therefore let us keep the feast, not with old leaven, neither with the leaven of malice and wickedness; but with the unleavened [bread] of with incorruption and truth.