Holy Days as a Discipline of the Pre-Nicene Church

This post is supposed to compile examples of support for Christian holy days and feast days in the early Church, especially of holy days from the modern Church calendar. I made this thread because I think the liturgical calendar is characteristic of the Catholic Church, and thus I think examples of this in the early Church can help show that the early Church was Catholic. So here are my examples, how about you guys? Does anyone know of any other examples of support for Christian feast days and holy days in the early Church?

~53 A.D. - Acts 18:21 Variant - “I must by all means keep this coming feast in Jerusalem.”

~55 A.D. - 1 Corinthians 5:7-8 -- “Christ our Passover has been sacrificed. Therefore let us keep the feast.”

~55 A.D. - 1 Corinthians 16:8 -- “But I will stay in Ephesus until Pentecost.”

~56 A.D. - Acts 20:16 -- “[Paul] was hastening to be at Jerusalem, if possible, on the day of Pentecost.”

~155 A.D. - St. Polycarp confers with Pope St. Anicetus about the different dates on which their communities celebrated Easter. “[T]hey immediately made peace with one another, not caring to quarrel over this matter. For neither could Anicetus persuade Polycarp...[nor] could Polycarp persuade Anicetus... But though matters were in this shape, they communed together... And they parted from each other in peace...maintaining the peace of the whole church.” (Irenaeus, On Easter, as quoted in Eusebius, Church History Book 5 Chapter 24 Paragraph 16-17)

~156 A.D. - “[As] opportunity is allowed us, with joy and rejoicing, the Lord shall grant us to celebrate the anniversary of [St. Polycarp's] martyrdom.” (Martyrdom of Polycarp Chapter 18)

~190 A.D. - Pope St. Victor orders the Eastern Catholic Churches to celebrate Easter only on a Sunday. A few of them refuse obedience, so he excommunicates them. He lifts the excommunication after St. Irenaeus points out that this is only a matter of discipline, not doctrine. (Eusebius, Church History Book 5 Chapters 23-24)

~190 A.D. - In regard to the excommunication mentioned above, St. Irenaeus writes to Pope St. Victor, “[T]he controversy is not only concerning the day, but also concerning the very manner of the fast. For some think that they should fast one day, others two, yet others more... Yet all of these lived none the less in peace, and we also live in peace with one another; and the disagreement in regard to the fast confirms the agreement in the faith.” (Irenaeus, On Easter, as quoted in Eusebius, Church History Book 5 Chapter 24 Paragraphs 12-13)

192 A.D. - Tertullian - “[We celebrate] on the day of the Lord’s Resurrection… Similarly, too, in the period of Pentecost; which period we distinguish by the same solemnity of exultation.” (On Prayer Chapter 23)

St. Clement of Alexandria wrote a lost work on Easter.

205 A.D. - Tertullian - “[Easter] affords a more than usually solemn day for baptism… After that, Pentecost is a most joyous space for conferring baptisms…[for] the day[s] of [Easter] and of Pentecost [are] properly a feast-day.” (On Baptism Chapter 19)

211 A.D. - Tertullian - “We rejoice in the same privilege also from Easter to Whitsunday.” (De Corona Chapter 3)

248 A.D. - Origen - “[We] ourselves are accustomed to observe certain days, as for example the Lord’s day, the Preparation, [Easter and] Pentecost...[but] the perfect Christian...is ever in his thoughts, words, and deeds serving his natural Lord.” (Contra Celsus Book 8 Chapter 22)

~250 A.D. - Commodianus - “[The clerks] will assemble together at Easter, that day of ours most blessed; and let them rejoice.” (The Instructions 75)

Before 280 A.D. - Anatolius of Alexandria writes his Easter Table, calculating the date of Easter out for many years.

325 A.D. - The First Ecumenical Council - “[L]et these synods be held, the one before Lent, (that the pure Gift may be offered to God after all bitterness has been put away), and let the second be held about autumn.” (Canon 5)

And: “We further proclaim to you the good news of the agreement concerning the holy Easter, that this particular also has through your prayers been rightly settled; so that all our brethren in the East who formerly followed the custom of the Jews are henceforth to celebrate the said most sacred feast of Easter at the same time with the Romans and yourselves and all those who have observed Easter from the beginning.” (Synodal Letter)