{Whose house are we} (hou oikos esmen h(886d)eis). We
Christians (Jew and Gentile) looked at as a whole, not as a local
organization. {If we hold fast} (ean katasch(936d)en). Condition of
third class with ean and second aorist (effective) active
subjunctive of katech(935c). This note of contingency and doubt runs
all through the Epistle. We are God's house if we do not play the
traitor and desert. {Boldness} (parr(8873)ian) {and glorying} (kai
kauch(886d)a) some had lost. The author makes no effort to reconcile
this warning with God's elective purpose. He is not exhorting
God, but these wavering Christians. All these are Pauline words.
B does not have mechri telous bebaian (firm unto the end), but
it is clearly genuine in verse  14 . He pleads for intelligent
confidence.