(a) Jeremiah had closely observed Israel's faithlessness towards their covenant with God and their apostasy in serving the useless gods of other nations. He diagnosed the fundamental reasons for their infidelity and unfaithfulness to God's covenant and attributed it to the fact that it was written in slabs of stone and thus, external. Although, the old covenant was sealed with the blood of animal, such blood was not capable of offering lasting union with God. Hence, Jeremiah introduced a new theory that unless man's soul unites with the spirit of God, no amount of verbal proclamation would produce a lasting effect. This is a new covenant because the heart of man is the only thing that can unite man with God. Under this new plan, the law would be written in people's individual hearts — unlike the old external law which was written on tablets of stone. According to Jeremiah, although God remained ever committed to His part of the covenant, Israel deviated. But if the new covenant comes from within, Jeremiah believed a lasting knowledge of God would result and God Himself would be their God.
Therefore, the need for any man to teach another to know the law would no longer be there and God would forgive their sins. He would gather His people from all the nations (from exile) and return them to Judah in safety. Henceforth, He would be their God, and they would be His people — both parties would remain faithful to each other.

(b) The Consequences of Israelites' breaking of God's covenant were:
(i) No escape from defeat and destruction by their enemies so long as they were unfaithful.
(ii) They would be forced into exile.
(iii) Famine and drought would be their lot in their homeland.
(iv) They would suffer national disgrace.