So is divorce a theological issue?
Divorce falls short of how God intends for us to behave. This is obvious in the Bible.
Is divorce the unpardonable sin?
No. This comes from Catholicism?
Does divorce and re-marriage keep a man from every being a pastor, deacon, teacher - ect?
Paul would generally suggest otherwise. If taken as a commandment as oppose to a suggestion, the answer to pastor and deacon should obviously be a no. I would leave this up to the church, but I would be very hesitant to join a church with a divorced and remarried pastor.
That being said, I also am hesitant to join churches where the pastor slept around for years fathering bastard children before "coming to Christ" and marrying a virginal wife. I may actually prefer the once-divorced man.
As far as teacher, do you mean religious or public school teacher?
May a man be a pastor if he is divorced, but not re-married?
Age of pastor and divorce matter. Can be better than remarriage. Once again I would be hesitant. See the answer above.
Why aren't you mentioning such things as cheating on your spouse?
Should a church ask about a prospective church member if he is divorced?
Why? Is the church into gossip?
If a man comes with a woman, it would be appropriate to ask if they are married. If a man comes alone, it should be assumed that he is single unless he wears a wedding ring. Asking single men or women if they have children when they come with none is always rude.
What leadership positions may a divorced (re-married or not) person hold in a church?
I don't think it's a definite prohibition as much as question of why? Why would churches have so much difficulty finding leaders who aren't divorced?
Is an annulment the same as a divorce for this purpose?
Annulment has a legal definition and an old one. The old definition means that the marriage is not consummated - no vaginal sex occurred. In my opinion and from what I have read in the Bible, if the marriage is not consummated, then there is no marriage.
But annulment is not the same as divorce.
If your church has a strict policy on divorce, then later a pastor wants to loosen it some - what would you do?
Are you talking about expulsion? Paul and the early church usually left expulsion to the worst offenses like sex with your mother. Even then they allowed return if the parties involved stopped doing evil.
any other points to bring up?
There isn't really a lack of pastors or deacons in the world. Why would a church insist on a divorcee? Perhaps divorce is so common, churches are having problems find people who are not divorced? If so, then wouldn't the church want a non-divorcee or simply single leader even more?