Were the Apostles etc. proclaiming “Jesus resurrected”?

The first Christians felt something very theologically significant happened on a Sunday (“The First day of the week”). This full article analyzes 2 evidences:
• Christians began calling Sunday “the Lord's day”
• Christians replaced the Sabbath with Sunday
This is relevant because Jews were otherwise tenacious about obeying the commandment concerning the Sabbath, and nothing other than their belief that Jesus resurrected on Sunday would warrant this change.

[Brackets] mean “forthcoming”

[Brackets] mean “forthcoming”

[Brackets] mean “forthcoming”

[Brackets] mean “forthcoming”

According to Paul's own testimony, he witnessed Jesus appearing to him alive from the dead. See this full article to analyze four examples: • In 1 Cor 9:1, Paul says “Have I not seen?” • In 1 Cor 15:8f, Paul says “He appeared to me” • Acts 9, 22, 26 etc. says so • In Gal 1:16, Paul says “revealed to me”

[Brackets] mean “forthcoming”