_Third_, the entire system or covenant based on the Aaronic priesthood has passed away and given place to a better covenant,—better in proportion to the firmer foundation on which the priesthood of Jesus rests.[130] Beyond question, the promises of God were steadfast. But men could not realise the glorious hope of their fulfilment, and that for two reasons. First, difficult conditions were imposed on fallible men. The worshipper might transgress in many points of ritual. His mediator, the priest, might err where error would be fatal to the result. Worshipper and priest, if they were thoughtful and pious men, would be haunted with the dread of having done wrong they knew not how or where, and be filled with dark forebodings. Confidence, especially full assurance, was not to be thought of. Second, Christ found it necessary to urge His disciples to believe in God. The misery of distrusting God Himself exists. Men think that He is such as they are; and, as they do not believe in themselves, their faith in God is a reed shaken by the wind. These wants were not adequately met by the old covenant. The conditions imposed perplexed men, and the revelation of God’s moral character and Fatherhood was not sufficiently clear to remove distrust. The Apostle directs attention to the strange absence of any swearing of an oath on the part of God when He instituted the Aaronic priesthood, or on the part of the priest at his consecration. Yet the kingship was confirmed by oath to David. In the new covenant, on the other hand, all such fears may be dismissed. For the only condition imposed is faith. In order to make faith easy and inspire men with courage, God appoints a Surety[131] for Himself. He offers His Son as Hostage, and thus guarantees the fulfilment of His promise. As the Man Jesus, the Son of God was delivered into the hands of men. “Of the better covenant Jesus is the Surety.” This will explain a word in the sixth chapter, which we were compelled at the time to put aside. For it is there said that God “mediated” with an oath.[132] We now understand that this means the appointment of Christ to be Surety of the fulfilment of God’s promises. The old covenant could offer no guarantee. It is true that it was ordained in the hands of a mediator. But it is also true that the mediator was no surety, inasmuch as those priests were made without an oath. Christ has been made Priest with an oath. Therefore He is, as Jesus, the Surety of a better covenant. In what respects the covenant is better, the Apostle will soon tell us. For the present, we only know that the foundation is stronger in proportion as the oath of God reveals more fully His sincerity and love, and renders it an easier thing for men laden with guilt to trust the promise.