Bishops or overseers, elders, and pastors are different titles for the same thing.
The feeding of the congregation or flock is the same as the pastoring or shepherding of the congregation or flock.
In his history of Baptists, D. B. Ray noted the following about Acts 20:28 in the KJV: "The word overseers in this passage is episcopous in the Greek--the word which is usually translated bishops; but to have rendered it bishops in this place, would have shown that elder and bishop is the same office, which would have condemned the church of the translators" (Baptist Succession, p. 292). Edward Hiscox quoted Henry Alford, Dean of Canterbury, as saying that the English Version [the KJV] "has hardly dealt fairly in this case with the sacred text in rendering episcopous, v. 28, overseers; whereas, it ought there, as in all other places, to have been bishops, that the fact of elders and bishops having been originally and apostolically synonymous, might be apparent to the English reader" (Principles and Practices for Baptist Churches, p. 90). If a Church of England Dean can in effect see the bias, why are KJV-only advocates unable to see it? Four times the KJV had translated the same word as bishops (Phil. 1:1, 1 Tim. 3:2, Titus 1:7, 1 Pet. 2:25). In Jamieson, Fausset, and Brown’s Commentary, David Brown asserted that the reason the word was not translated “bishops” at Acts 20:28 was “to avoid the obvious inference that the same persons are here called ‘elders’ (v. 17) and ‘bishops’” (III, p. 150). John Eadie wrote: “It has also been alleged, and not without some reason, that in Acts 20:28, the rendering of the clause ‘over the which the Holy Ghost hath made you overseers’ is a deflection from the true translation, and conceals the identity of the ‘elders’ with the office-bearers usually named ‘bishops’” (English Bible, II, p. 271). James Lillie wrote: “Because had it there (Acts 20:28) been rendered bishop, everyone would have seen, that in the one Church of Ephesus, there were several bishops. In that one text alone, therefore, the word is translated, not as everywhere else, transferred, because, there, dust had to be thrown into the common reader’s eyes, lest he should discern the unscriptural nature of English Church government” (Bishops, p. 186). In The Expositor as edited by Samuel Cox, this is stated: ‘It can hardly be doubted that the translators avoided the word ‘Bishops’ in Acts 20:28 and put ‘overseers’ instead, because otherwise it would have been obvious that in the Apostolic age the word ‘presbyter’ and ‘bishop’ were practically identical” (Vol. III, p. 301). John Beard suggested that the KJV translators saw that the use of “bishops” at Acts 20:28 would have acknowledged that “plain presbyters were the same as bishops” (Revised English Bible, p. 80). Jack Lewis wrote: “It has been thought that the varied use of ’bishoprick’ (Acts 1:20), ’overseers’ (Acts 20:28), ’oversight’ (1 Pet. 5:2), and ’bishop’ (1 Tim. 3:1) was an effort to avoid identification of bishops and elders” (English Bible, p. 63). John McClintock and James Strong agreed that the use of overseers at Acts 20:28 was “in order to avoid the identification of bishops and elders” (Cyclopaedia, III, p. 218).
John Cotton (1584-1652) affirmed that Paul “called for the elders of Ephesus, Acts 20:17, whom also he named Bishops, for so the Greek word is, which is translated overseers, verse 28” (Way, p. 47). Calibute Downing (1604-1643), who was a son-in-law of KJV translator Richard Brett, referred to “elders or parochial bishops, or bishops of particular congregations; Acts 20:17, 28” (Clear Antithesis, pp. 1-2). John Davenport (1597-1670) noted that “those whom Luke calls elders, in Acts 20:17, Paul calls Bishops in verse 28” (Power, p. 79). In his 1699 book, Thomas Forrester agreed that Paul described “the elders of that one city [Ephesus] as Bishops” (Hierarchical Bishops, p. 68). In 1688, David Clarkson affirmed that “elders of the church who are said verse 28 to be made Bishops by the Holy Ghost” (Primitive Episcopacy, p. 10). Francis Turretin noted that “the Ephesian pastors who are said to be presbyters are also called bishops (Acts 20:28)“ (Institutes, III, pp. 201-202). Edward Litton noted that “the same persons, whom, at verse 28, St. Paul calls ‘bishops’ are described by St. Luke, at verse 17, as ‘the presbyters of the church’ of Ephesus” (Church, p. 287). Thomas Smyth observed that “on this occasion, Paul formally enjoined upon its presbyters to continue to act as bishops, and to govern that church of which the Holy Ghost had constituted them the bishops” (Presbytery, p. 260). Concerning Acts 20:17, 28, George Campbell wrote: “Here there can be no question that the same persons are denominated presbyters and bishops” (Lectures on Ecclesiastical, p. 72). Henry Alford observed: “For ‘overseers,‘ bishops; elders and bishops, in the primitive Church, were the same” (How to Study, p. 351). Ralph Wardlaw commented: “overseers--the same word as that usually translated bishops” (Congregational Independency, p. 176). Zodhiates noted that “the elders of Acts 20:17” at verse 28 “are called bishops” (Complete Word Study, p. 635). The 1380's Wycliffe's, the 1535 Coverdale's Bible, the 1538 Coverdale's Duoglott New Testament, and 1582 Rheims had rendered it "bishops" in this verse while the other pre-1611 English Bibles had “overseers.” An edition of the KJV printed in London in 1660 has this marginal note for “overseers”: “Or bishops.“ In his note on Acts 20:28, Diodati indicated that the Italian Bible has “bishops” at its rendering. One source in 1871, Thomas Abbott observed that it had been “stated that this rendering [overseers] was due to Bancroft’s influence,” but he asserted that it was “erroneously stated” because the rendering “occurs in Tyndale who cannot be suspected of high prelatic notions” (English Bible, p. 42). Since this verse is not given as one the examples of the 14 changes in Hill’s 1648 sermon and is also not mentioned in the 1671 book about Henry Jessey, this reference could indicate that there were other sources about them available to authors in the 1800’s.
Would the rendering “bishops” [plural] at Acts 20:28 for several “elders” [plural] of a church [singular] at one city (Acts 20:17) have been a problem for the prelatic or Episcopal church government view that each bishop is over a diocese or district that may include several churches and that a bishop has authority over elders or pastors? Webster’s New Twentieth Century Dictionary gave as its second definition for bishop the following: “in the churches maintaining apostolic succession, a prelate superior to the priesthood, consecrated for the spiritual government and direction of a diocese, bishopric, or see” (p. 187). Would use of the rendering “bishops” at Acts 20:28 have conflicted with the hierarchical or prelatic sense or definition of the diocesan bishop? Would not “bishops” have been one of the ecclesiastical words according to the third rule to be used and kept unless its use at this verse in the genuine prelatic sense was considered a problem for the prelates? Would use of “bishops” at Act 20:28 have demonstrated to English readers that “bishops” and “elders” were names for the same office and that these were not diocesan bishops? Was “overseers” used at Acts 20:28 in order to prevent English readers from seeing the error of the Episcopal claim that a bishop was superior to an elder? David Calderwood (1575-1650) maintained that “the prelate maketh a confusion of names that he may put himself in the place of the apostle” (Pastor and the Prelate, p. 21). Calderwood noted that “the question is not of the bishop, but of the prelate or diocesan bishop, whether he be the divine bishop” (p. 33). Calderwood observed that “the diocesan bishop is but one, in a diocese, over many kirks [churches]“ (p. 33). Calderwood asserted that “the diocesan bishop hath no particular congregation for his flock” (p. 34). John Davenport maintained: “Not one bishop over many churches, but many bishops over one church; not diocesan but congregational bishops” (Power, p. 79). Calibute Downing referred to prelates as “diocesan Lord Bishops, lording over their brethren contrary to Christ’s forbidding” (Clear, pp. 1-2). At the entry for “bishop,“ Samuel Green asserted that “Diocesan bishops are not known in the New Testament” (Biblical and Theological Dictionary). William Ames (1576-1633) wrote: “Ordinary ministers conform to the instituted church and are not ecumenical, national, provincial, or diocesan bishops, but rather elders of one congregation. In the same sense they are also called bishops in the Scriptures” (Marrow, p. 209). Ralph Earle wrote: “Turning to the NT, we discover one fact immediately: there is no mention of any diocesan bishop” (Word Meanings, p. 389). In his commentary on Acts, John Phillips maintained that “the word [episkipos] does not envision an Episcopal hierarchy” (p. 405). What advantage or gain was provided to English readers by translating the Greek word as “overseers” only at Acts 20:28 besides the obvious gain to those who advocated Episcopal church government?