δοκιμάζειν, [2 verses]](verb pres inf act) "Discern" is from dokimazo , which means "to assay", "to evaluate," "to test", "to prove for onesself", "put a person to the test", "approve", "sanction", "approve for political office", and "pass as fit for office". -- The Greek verb translated as "discern"  means "to assay","to evaluate," "to test", "approve for political office", and "pass as fit for office".  This is the core of the double meaning here, the play between "test" and "approve for office", the first applied to the weather, the second to Jesus himself. This is the first time this word is used by Jesus and it is only used twice.