The missionaries confined their labors to the Galatian province on this trip. They did not move farther east into the kingdom of Antiochus or the province of Cilicia that Paul may have evangelized previously during his time in Tarsus. Tarsus stood some160 miles east of Derbe. Instead they retraced their steps to encourage, instruct, and organize the new converts (cf. Acts 18:23). [1] Apparently they did more discipleship than evangelism on this return trip to the cities where the apostles" lives had been in danger. They warned the new converts that they too should expect persecution (cf. Galatians 4:13; Galatians 6:17; 2 Timothy 3:11). The "kingdom of God" evidently refers to the messianic kingdom. Entrance into it was still future for these disciples when the missionaries gave them this exhortation. Though Christians will not go through the Tribulation, we will experience tribulation before we enter the Millennium ( 2 Timothy 3:12). [source][source][source]