God relates to humankind through Covenant.
There is an historical continuity of God’s covenant relationship with mankind, expressed through various administrations (e.g. Adamic, Noahic, Abrahamic, Mosaic, Davidic, Messianic), beginning in Adam and culminating in Christ.
Significantly, there is a five-fold covenant structure that provides the ground of God’s dealings with man, from the individual, through families, the redeemed community, to nations. This structure not only exists in books of the Bible (e.g. Deuteronomy, Revelation) but also throughout ancient near-eastern cultures. It can be conveniently remembered through the acronym THEOS: Transcendence, Hierarchy, Ethics, Oath, Succession. All the covenants of antiquity between a victorious king and his vassals were according to this pattern. It establishes the authority of the king (transcendence, hierarchy), outlining the conditions of it (ethics), the penal consequences of rebellion (oath), and its future continuity (succession). While all God’s dealings with man are imbued with his paternal heart, he has enthroned his Son as the victorious King and we are his vassals. We are now under his government. And just as every civil government of man has a legal constitution, likewise, God’s government (i.e. the kingdom of God); its constitution is the covenant with its stipulations (conditions–ethics) and sanctions (consequences–oath). Covenant fidelity, therefore, either invites the blessing of God and human flourishing. Or conversely, covenant infidelity invites historical judgements and human suffering—God’s remedial disciplines.
Covenant is thus the core motif of the Bible. Without understanding it and how it functions we are biblically illiterate.
God’s nature nor purpose have changed; covenant continuity flows into the 21st century with full ethical force for all societies and nations.
Consequently, Covenant and Kingdom are motifs joined at the hip—the kingdom of God comes to the earth through covenant obedience.