Kingdom of God
The kingdom comes through the ministry of Jesus and the preaching of the gospel in all the world. It is both the reign and the realm of God for, although in the present age the locus of the kingdom in the world is diffuse, it is defined by the presence of Jesus at the right hand of the Father. It is both present and future until its consummation at Jesusâ€™ return. It is also at least one possible theme by which biblical theology can be integrated. It is the focus of both creation and redemption: Godâ€™s plan of redemption is to bring in a new creation. The entire biblical story, despite its great diversity of forms and foci, is consistent in its emphasis on the reign of God over his people in the environment he creates for them.
Graeme Goldsworthy (New Dictionary of Biblical Theology, pg. 620)
The kingdom of God is the rule of an eternal sovereign God over all creatures and things (Ps. 103:19; Dan. 4:3). The kingdom of God is also the designation for the sphere of salvation entered into at the new birth (John 3:5-7).