New Testament...

Luke 10:1-2
10:1 After these things the Lord appointed other seventy also, and sent them two and two before his face, into every city and place where he himself would come.


    By Revelation...

DC 104:13
104:13a The Seventy are to act in the name of the Lord, under the direction of the Twelve, or the traveling high council, in building up the church, and regulating all the affairs of the same, in all nations; first unto the Gentiles, and then to the Jews;