The importance of this oath is explained in the above-mentioned intervention. Like the covenant with Noah, God`s covenant with Abraham is an eternal covenant: “I will establish after you my covenant between you and you and your posterity after you, for a perpetual covenant, to be God for you and for your descendants after you” (Genesis 17:7). The covenant between God and the Jews is the basis of the idea of the Jews as a chosen people. But the Abrahamic covenant depended on God saying, “Live in my presence and be innocent.” (G 17:1). Thus, if they are not innocent and live in the presence of God, the covenant will not be realized. It is also mentioned in gene 15.1 that “your reward will be very great”. It is a reward for them if they walk in the Lord. This is what the Jews misunderstood in Jesus` day. They felt that the covenent was unconditional and that because they were the descendants of Abraham, they were protected. They forgot that it was common for them to fulfill their part of life in the presence of God and to be innocent.
Now, with the new covenant, it is alsoitional that men must accept that Jesus died for their sins and must turn back. Jesus` death and resurrection eliminated the sin of men caused by their failure to walk flawlessly: but only if they accept and choose in grace. Only then will they be saved. The covenant between Abraham and God consisted of three distinct parts: thus, two different covenants were made between God and Abraham. The first (Gen 15) guaranteed God`s promise to make Abraham a “great nation.” The second (anticipated at Gen 17 and ratified at Gen 22 by a divine oath) confirmed God`s promise to bless all nations through Abraham and his “descendants.” Not only does Jesus exercise a permanent, perfect, and heavenly priesthood (Heb 7:23–8:6), but the covenant of which he mediates, “is based on better promises” (Heb 8:6b), explained in terms of “eternal redemption” (9:12) and an “eternal inheritance” (9:15) that is assured by the blood of Christ (Heb 9:11–10:18) – later described as “the blood of the eternal covenant” (Hebrews 13:20). Like Paul, therefore, the contrast is not between something bad and something good, but between something good (but temporal) and something better (because unlike the old covenant, novelty is unbreakable and eternal…”