{Let us hold fast} (katech(936d)en). Present (keep on holding
fast) active volitive subjunctive of katech(935c) as in  3:6,14 .
{That it waver not} (aklin(885c)). Common compound adjective (alpha
privative and klin(935c), unwavering, not leaning, here only in N.T.
It is a confession of hope, not of despair. {That promised} (ho
epaggeilamenos). First aorist middle articular participle of
epaggell(935c). This is the argument remaining to be discussed
( 10:26-12:3 ) and already alluded to ( 6:13f.  8:6 ). The
ministry of Jesus rests upon "better promises." How better? God
is "faithful," but he made the other promises also. We shall see.