I agree of course some doctrines that are extremely defiant of Gods word and evidently obvious should be denied and debated against.
But these core doctrines have held Christianity and Christians together for centuries. We may create denominations over the in depth theology on core doctrine but we should still unite against the dangers of secularism and destructive religions.
We in this day and age cannot afford to divide if we can help it. Scripture says to judge them by their fruit. I look at Christians or churches with different theological beliefs and then look at the fruit. Studying the fruit often causes me to be less judgmental and more forgiving.
I can understand that at some level, but having worked in interdenominational parachurch ministries, I can tell you it is VERY HARD.
For instance, I worked in jail ministry. The chaplain was a nutty charismatic who told prisoners that God talked to him audibly, and wanted to exorcise them from generational sins.
In meetings with me, these topics were brought up by the prisoners. They wanted to know what I thought about it. So, what do I say?
My view is that the chaplain has mental issues or is a liar. Do I tell them that?
I finally left this ministry because 1) the guards harrassed me because they thought I was trafficking or something because I took the initiative of buying Christian books for prisoners because I knew they were hearing trash from other chaplain aides 2) the chaplains didn't care for me because I was against their kookiness which included radical KJV Onlyism, charismania, and nutty prophecy stuff 3) the prisoners themselves damaged books that I bought, using them for scratch writing paper, and I had to listen to demonic talk from child molesters on occasion.
And, as I read the newspaper, I see over and over again, guys that I thought were saved returning back to their filthy language, sexual immorality, and drug abuse....these were guys I thought exhibited some signs of being regenerated.
And, of course, the charismatic chaplain concluded these guys were saved, and are now lost. I didn't know what to think personally.
I can think of two guys in two years of doing jail ministry that I still have high hopes for. That's a pretty low yield concerning the amount of money I invested in giving materials.
But, anyways, I'm getting off track...it is REALLY hard to work with other Christians who don't share a common doctrinal basis due to the factors I have mentioned to you.
In theory, though, I agree with you...the practice is really hard, though.
Are you aware that George Whitefield was "sold out" by his friends, the Wesley brothers, and declared to hold a sub-biblical theology?
As soon as he left England to preach in the USA, the Wesleys filled in the gap left by him, at his recommendation, and started denouncing him for Reformed theology. Whitefield was very patient and forgiving towards them, but I can tell you for sure I wouldn't trust a free-willer in ministry.
Like I said, though, in theory I agree with you 100%. In practice, though, I've found that sectarianism within a common ministry doesn't work.