This is the second "faithful Word" of these letters to Timothy and Titus - "the Control of the Church", describing the character of he who wants to be recognized as a bishop or elder in a local church.
Note that, in apostolic churches, bishops and elders are the same people (see Acts 20:17, 28) and there was a plurality of them in each church. There were elders among the believers in Jerusalem (Acts 11:30; 15:2,4,6,22,23); we do not read that the apostles “appointed” them; in Acts 14:23, Paul and Barnabas "appointed" elders in churches that they themselves had founded (Derbe, Lystra, Iconium and Antioch); and Paul sent Titus to "set in order the things that are lacking" and to "appoint elders in every city", according to the character required (Titus 1: 5-9).
Today we have no apostles or “apostolic delegates" to appoint elders (bishops), but in these epistles have the characteristics by which we can recognize brethren that the Holy Spirit marked for this "good work" (v. 1), which requires well distinguished qualities of a christian character.
The word "deacon" in the Bible simply means "a servant" and came to be applied to brethren (and sisters) who served the church in a given and recognized capacity - such as treasurer, secretary, librarian, and host. It is generally understood that such a service is of material nature, however done by pious and spiritual believers ("filled with the Holy Spirit" and of "good reputation"-Acts 6:3):
Note: We could increase the comments on these essential qualities for bishops and deacons, however there is only one point that we want to add: such qualities do not describe special or exceptional gifts possessed solely by elders or deacons. On the contrary, they are qualities that belong to the common christian life; they could be considered as subjects for exhortations to the believers in general, because "to be irreproachable" in their Christian character should be the target of every believer.
Paul expected to see Timothy "soon", but wrote this letter to emphasise the importance of a right conduct in those forming the Church of God, which is the great witness of God in the world, being the "House of God", teaching and defending the Truth.
The Lord Jesus Christ is the “Godliness" (v. 16) personified and historically revealed to men:
a) the incarnation: the Son of God made Himself man (John 1:14);
b) justified: vindicated as the Righteous (Mark 9:7; Luke 23:47);
c) seen by angels: birth; Gethsemane; resurrection; ascension;
d) preached: among the nations, by the Gospel;
e) believed: by the universal church;
f) received in glory: on the throne of God (Acts 1:11; 7:56).
This summarizes the triumphant career of the Lord Jesus, the Messiah, God in the flesh, Saviour of the world and Head of His Church.
1 This is a faithful saying: If a man desires the position of a bishop, he desires a good work.
2 A bishop then must be blameless, the husband of one wife, temperate, sober-minded, of good behavior, hospitable, able to teach;
3 not given to wine, not violent, not greedy for money, but gentle, not quarrelsome, not covetous;
4 one who rules his own house well, having his children in submission with all reverence
5 (for if a man does not know how to rule his own house, how will he take care of the church of God?);
6 not a novice, lest being puffed up with pride he fall into the same condemnation as the devil.
7 Moreover he must have a good testimony among those who are outside, lest he fall into reproach and the snare of the devil.
8 Likewise deacons must be reverent, not double-tongued, not given to much wine, not greedy for money,
9 holding the mystery of the faith with a pure conscience.
10 But let these also first be tested; then let them serve as deacons, being found blameless.
11 Likewise, their wives must be reverent, not slanderers, temperate, faithful in all things.
12 Let deacons be the husbands of one wife, ruling their children and their own houses well.
13 For those who have served well as deacons obtain for themselves a good standing and great boldness in the faith which is in Christ Jesus.
14 These things I write to you, though I hope to come to you shortly;
15 but if I am delayed, I write so that you may know how you ought to conduct yourself in the house of God, which is the church of the living God, the pillar and ground of the truth.
16 And without controversy great is the mystery of godliness: God was manifested in the flesh, Justified in the Spirit, Seen by angels, Preached among the Gentiles, Believed on in the world, Received up in glory.
1 Timothy chapter 3