the likely reason why fasting later became associated with the run-up to Easter is that people started holding baptisms at Easter. The three-week long preparation for becoming a Christian through baptism included fasting, and as baptism became more strongly associated with Easter in the fourth century AD, it is possible that fasting in the lead-up became more generalised to include people who were already Christians

Peter I of Alexandria in the fourth century who connected Christian penitential (still not Lenten) fasting to Jesus’s 40-day fast in the wilderness:

earliest reference to a sustained fast of more than two or three days is in the Didascalia, a Syrian Christian document probably from the the third century AD. Therefore you shall fast in the days of the Pascha from the tenth, which is the second day of the week; and you shall sustain yourselves with bread and salt and water only, at the ninth hour, until the fifth day of the week. But on the Friday and on the Sabbath fast wholly, and taste nothing … For thus did we also fast, when our Lord suffered, for a testimony of the three days … This text connects a six-day fast with Easter and with Jesus’s suffering, but surprisingly still not with Jesus’s 40-day temptation

John Chrysostom (c. 349-407), writing against Christians sharing anything in common with Jews, admonishes Christians who fast on the Jewish Day of Atonement, Yom Kippur

the Psalms of Solomon 3:8–9 describe fasting as a way to atone for sins and as a habitual practice of the righteous.

it was only after Christians began to fast specifically prior to Easter, about 300 years after Jesus’s death, that anyone looked to the Bible to find a source for the practice

As for patristic writers, they constantly called attention to the fact that a presbyter and bishop held one and the same office in the primitive church, and that they were different descriptions for it. The quotes from the early church father Jerome are the most numerous in this respect. Particularly interesting is Jerome's exegesis of Titus... Jerome (347-420): A presbyter, therefore, is the same as a bishop, and before dissensions were introduced into religion by the instigation of the devil, and it was said among the peoples, ‘I am of Paul, I am of Apollos, and I of Cephas,’ Churches were governed by a common council of presbyters; afterwards, when everyone thought that those whom he had baptised were his own, and not Christ’s, it was decreed in the whole world that one chosen out of the presbyters should be placed over the rest, and to whom all care of the Church should belong, that the seeds of schisms might be plucked up. Whosoever thinks that there is no proof from Scripture, but that this is my opinion, that a presbyter and bishop are the same, and that one is a title of age, the other of office, let him read the words of the apostle to the Philippians, saying, ‘Paul and Timotheus, servants of Christ to all the saints in Christ Jesus which are at Philippi with the bishops and deacons.’ John Harrison, Whose Are the Fathers? (London: Longmans, Green and Co., 1867), p.488. See also Karl Von Hase, Handbook to the Controversy with Rome, trans. A. W. Streane, Vol. 1, 2nd ed. rev. (London: The Religious Tract Society, 1909), p. 164. Cited also by Calvin, Institutes of the Christian Religion, Vol. 2, ed. John T. McNeill and trans. Ford Lewis Battles (Philadelphia: The Westminster Press, reprinted 1977), IV.4.2, pp. 1069-1070. Latin text: Idem est ergo presbyter qui et episcopus, et antequam diaboli instinctu, studia in religione fierent, et diceretur in populis: Ego sum Pauli, ego Apollo, ego autem Cephae, communi presbyterorum consilio, Ecclesiae gubernabantur. Postquam vero unusquisque eos quos baptizaverat suos putabat esse, non Christi, in toto orbe decretum est, ut unus de presbyteris electus superponeretur caeteris, ad quem omnis Ecclesiae cura pertineret, et schismatum semina tollerentur. Putet aliquis non Scripturarum, sed nostram esse sententiam, episcopum et presbyterum unum esse, et aliud aetatis, aliud esse nomen officii: relegat Apostoli ad Philippenses verba dicentis: Paulus et Timothaeus servi Jesu Christi, omnibus sanctis in Christo Jesu, qui sunt Philippis, cum episcopis et diaconis, gratia vobis et pax, et reliqua. Commentariorum In Epistolam Ad Titum, PL 26:562-563. Jerome (347-420): Therefore, as we have shown, among the ancients presbyters were the same as bishops; but by degrees, that the plants of dissension might be rooted up, all responsibility was transferred to one person. Therefore, as the presbyters know that it is by the custom of the Church that they are to be subject to him who is placed over them so let the bishops know that they are above presbyters rather by custom than by Divine appointment, and ought to rule the Church in common, following the example of Moses, who, when he alone had power to preside over the people Israel, chose seventy, with the assistance of whom he might judge the people. We see therefore what kind of presbyter or bishop should be ordained. John Harrison, Whose Are the Fathers? (London: Longmans, Green and Co., 1867), p.488. See also Karl Von Hase, Handbook to the Controversy with Rome, trans. A. W. Streane, Vol. 1, 2nd ed. rev. (London: The Religious Tract Society, 1909), p. 164. Latin text: Haec propterea, ut ostenderemus apud veteres eosdem fuisse presbyteros quos et episcopos: paulatim vero ut dissensionum plantaria evellerentur, ad unum omnem sollicitudinem esse delatam. Sicut ergo presbyteri sciunt se ex Ecclesiae consuetudine ei qui sibi praepositus fuerit, esse subjectos: ita episcopi noverint se magis consuetudine, quam dispositionis Dominicae veritate, presbyteris esse majores, et in commune debere Ecclesiam regere, imitantes Moysen, qui cum haberet in potestate solum praeesse populo Israel, septuaginta elegit, cum quibus populum judicaret. Videamus igitur qualis presbyter, sive episcopus ordinandus sit. Commentariorum In Epistolam Ad Titum, PL 26:563.Click to expand... Theodoret of Cyrrhus (393-466), an eastern father this time, in his commentaries on 1 Timothy and Titus, makes essentially the same point as that of Jerome. For example, while commenting on 1 Timothy 3:1 he says, "By overseer here he (Paul) means elder, as we demonstrated in commenting on the letter to the Philippians. Here, too, it is very easy to grasp this: after the laws for overseers he puts in writing those for deacons, making no mention of the elders. But, as I remarked, at that time they were in the habit of calling the same people overseers and elders, whereas to those now called overseers they gave the name apostles." And then later in his commentary on Titus 1:7, Theodoret wrote, "From this it is clear that they called the elders overseers: after saying, that you might appoint elders in every city, he went on, An overseer, you see, must be above reproach. Now it was the custom for there to be in each city a number, not of bishops, but of elders." See Robert Charles Hill, Theodoret of Cyrus: Commentary on the Letters of St. Paul, Vol. 2 (Brookline: Holy Cross Orthodox Press, 2001), pp. 216-217, 253.

Parishes that distribute Holy Communion only under the species of bread

both Jews and Gentiles in the early church had backgrounds that included fasting, and the early community incorporated the practice for similar, but often reinterpreted, reasons.