J. Herbert Kane, missionary and missiologist, wrote the following: "God is a missionary God. The Bible is a missionary book. The Gospel is a missionary message. The church is a missionary institution. And when the church ceases to be missionary minded, it has denied the faith and betrayed its trust.”
In the Old Testament, when God began to draw a covenant people (Israel) to himself, He was clear that Israel’s ultimate purpose was that of blessing the nations and drawing them in to worship him. God’s covenant with Abraham included the promise that “in you all the families of the earth shall be blessed.” (Gen. 12.3, ESV) He consistently reminds Israel of its Abrahamic mandate to bless all the nations: “It is too light a thing that you should be my servant to raise up the tribes of Jacob and to bring back the preserved of Israel; I will make you as a light for the nations, that my salvation may reach to the end of the earth.” (Isaiah 49.6, ESV)
God also repeatedly commanded Israel to love the foreigners in its midst: “You shall not oppress a resident alien; you know the heart of an alien, for you were aliens in the land of Egypt.” (Ex. 23.9, NRSV)
In the New Testament, Jesus’ last commands (cf. Matt. 28.18-20 and Acts 1:8) dealt with the disciples’ missions of global disciplemaking.
Space prohibits an exhaustive treatment of this topic. For more in-depth study, consult Jeff Lewis’ God’s Heart for the Nations, Every Ethne’s Launch course, and the Perspectives course.
Also, visit additional Propempo.com articles below. All of these together give you a good idea of what the Bible says about missions.