"I entreat Euodia and I entreat Syntyche to agree in the Lord". ESV
In the next verse we are told Euodia and Syntyche "laboured side by side with me in the gospel" and also that their "names are in the book of life", so "agree in the Lord" is referring to Christians.
We are not told what their disagreement was about but as the entreaties were public so too was probably the disagreement.
What would have to happen for them to "agree in the Lord"?
A. Must they publicly announce that they had stopped arguing. Though in private they still totally disagreed with each other?
B. Or must one of them say that for the sake of peace they agreed with the other, though it made no sense to them, but they were prepared to step out in faith?
C. Must one or both of them change their beliefs until they exactly match each others?
D. Another possibility?
E. Is it significant that Paul entreats each of them separately, in that "parakalo" comes twice?