Rev. Dr. Timothy Keller: 5 counter-cultural practices of early church

The early church was also counter-cultural when it came to divorce & remarriage. While non-Christian Jews and the pagans of the Roman Empire permitted remarriage after divorce even while the former spouse was alive, Christians obeyed the commands of Jesus and the apostles and refrained from remarriage while their former spouse was alive.

https://tinyurl.com/can-I-divorce-and-remarry

However, most Protestant churches reject the commands of Jesus and the apostles and permit remarriage even when the former spouse is still alive.