Titus 1:5-9 This is why I left you in Crete, so that you might put what remained into order, and appoint elders in every town as I directed you—if anyone is above reproach, the husband of one wife, and his children are believers and not open to the charge of debauchery or insubordination. For an overseer, as God's steward, must be above reproach. He must not be arrogant or quick-tempered or a drunkard or violent or greedy for gain, but hospitable, a lover of good, self-controlled, upright, holy, and disciplined. He must hold firm to the trustworthy word as taught, so that he may be able to give instruction in sound doctrine and also to rebuke those who contradict it.
In the NT churches, there seems to be only one order of spiritual leadership in the local churches--elders (v.5). Elders (presbuteros, literally elderly) are also called called "overseer" (v.7, episkopos; KJV: "bishop"). The mainline churches have split this one order of church leadership into two: elder and bishop. Together with the deacons, it becomes a 3-level leadership, with the "bishop" at the top, overseeing the elders and deacons.
But in the context of Titus 1, the elder is the overseer ("bishop"). When Paul uses the word "elder", he is emphasizing the leader's character, viz,. his spiritual and moral maturity. However, when he uses the word "overseer", he is emphasizing the leader's function, viz., providing spiritual and moral oversight and direction to the flock of younger believers.
In fact, even the word "pastor" was not a separate category, but essentially emphasizes the elder's shepherding or feeding function. In Acts 20:17, we are told that Paul called for a meeting of the Ephesian elders at Miletus. But he described them as "overseers" appointed by the Holy Spirit in verse 28 and exhort them to feed (poimano, literally, to shepherd or pastor) the church of God. So the elders are a group of spiritually and morally matured leaders who provides spiritual oversight for the congregation and also feed (pastor) them. The word "pastor" is used only once in the NT and it is found in Ephesians 4:11, "pastors and teachers". It refers to pastor as one of the gifts given to the church, referring to the ability to feed God's flock with the word of God.
But the "pastor" is not a position, but a gift and a function. So strictly speaking, there is only one category of spiritual leadership of the church: elders who provide oversight (overseers) and feed (shepherds) the flock supported by deacons to take care of administrative and logistical matters. While modern bishops may provide the apostolic function of overseeing churches, they are never to dictate the direction of the local churches provided by the elders.
Be that as it may, what matters most is spiritual and moral character in church leadership. The best indicator of this qualification is in how the elder runs his home: how he treats his wife and how he manages his children: "if anyone is above reproach, the husband of one wife, and his children are believers and not open to the charge of debauchery or insubordination" (v.6). Elders should not be appointed based on their professional life but on their family life. Their "success" in the workplaces may not be translated into success in the homes. The church of God is more like a family than a business enterprise. So, a church elder must "not be arrogant or quick-tempered or a drunkard or violent or greedy for gain, but hospitable, a lover of good, self-controlled, upright, holy, and disciplined" (v.7-8). Grace is not an excuse for lowering the spiritual and moral standards expected of church leadership.
It is only when the elder has such spiritual and moral character that he is fit to "give instruction in sound doctrine and also to rebuke those who contradict it" (v.9). Without the foundation of spiritual and moral character, our teaching will sound hollow to the hearers.
Father, grant in every church of Yours elders and deacons who are beyond reproach spiritually and morally. Amen.