ANSWER: It refers not to extent of time, but the thoroughness of the salvation. The Greek (παντελης) properly means ''unto completeness,'' perfectly, utterly. See R. V. Margin. "Well does Delitzsch say, "Christ is able to save in every way, in all respects, unto the uttermost; so that every want and need, in all its breadth and depth, is utterly done away." He calls it "an all-embracing salvation for those who in faith make use of the way of access which he has opened by the removal of the barrier of sin."
— Steele's Answers p. 79