Paul's strategy for church planting included the eventual selection of leaders from among the converts to oversee the ministry and spiritual growth of the community (compare Acts 14:23). In this way the missionaries could move on freely to expand the work in new and unreached areas. As Paul's team of trained coworkers grew, he entrusted a good deal of the work to them. In the case of the Cretan churches, Titus functioned in this capacity.
Paul spells out his purpose in appointing Titus to the work in Crete in verse 5. It has two parts. The first phrase Paul uses to describe this purpose might address the need for correction (of things gone wrong) or completion (of things as yet undone). The former possibility makes sense in view of the false teaching that Titus is to combat (vv. 10-16). But the second part of the purpose, to appoint elders, and the phrase "what is lacking" in the first part suggest that Paul means completion of the tasks that remain to be completed. Actually, since correcting the false teachers is linked to careful choice of leadership (v. 9), it may be best to combine the two possibilities as the NIV has done: straighten out what was left unfinished.
In any case, the second part of the purpose is clearly first on Paul's list of specific things that Titus is to finish. Precisely what went into the process of appointing elders is not clear. Certainly from the qualifications that follow we can guess that some form of evaluation played a part. But the situation in Crete, where the churches were younger, was not the same as that which we find in Ephesus, where a body of elders already existed (see 1 Tim 4:14). And any evaluation may have been carried out by Titus himself (compare Acts 14:23). The appointment of the elders would have been signaled by the laying on of hands (compare Acts 14:23; 1 Tim 4:14; 5:22) in the presence of the congregation. It is also impossible to determine how many elders would have been selected in every town (meaning "in the house church of each town"); but the general rule would probably have been a plurality of leaders.
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