Commentaries:
Robertson's Word Pictures (NT)
But abide thou (su de mene). Emphatic contrast (su de), "But thou." Present active imperative of menw, common verb, to remain.
In the things which (en oiv). The antecedent to oiv is not expressed ("in which things") and the relative is attracted from a accusative with emaqev (didst learn, second aorist active indicative of manqanw) to the case of the unexpressed antecedent (locative with en).
Hast been assured of (epistwqhv). First aorist passive indicative of pistow, old verb (from pistov, faithful), to make reliable, only here in N.T.
Knowing from whom (eidwv para tinwn). Second perfect active participle of oida. Note tinwn (ablative case after para in an indirect question). The list included the O.T. prophets, Paul, Eunice, Lois. There ought to be moral authority in such personages.
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