βλητέον. [1 verse] (adj sg masc acc) "Must be put" is bleteos, which is defined from the translation of this verse as "one must throw," or "one must put." However, the verb root,  ballo, means "pour" when uses with liquids so that works better here. However, this word only occurs once in ancient Greek, in this verse so this is the only precedent for translation. It definition is taken from the meaning of the verb ballo that is used in Matthew 9:17. There is nothing here that indicates a meaning of "must." In the Latin Vulgate, a verbal adjective is used. It is definitely not an active verb as used here. Though it is not a normal participle form of the root, which means "toss," it seems like "tossing," a verbal adjective form of the root works best.