It is usually the synergist's contention that the following are true:
-God is doing everything He can to keep people out of hell
-God wishes that every single human being escape hell and end up in heaven
-God treats everyone perfectly equally for the sake of fairness, regarding their salvation
If those are all true, I have some questions for my synergist brothers and sisters:
1) God foreknew whether every single person in the race would believe or not, before he created them. For example, God knew that if he created Bob, Bob would never believe and end up in hell. Why did God create Bob, then? If God doesn't want any human being to end up in hell, why didn't God only create those human beings he foreknew would willingly believe? That way, he'd have an entire human race of willing believers, and nobody in hell.
2) Why do some people die earlier than others? Some people die at age 15 in tragic car accidents, before they had a chance to give the gospel some consideration and submit to Jesus. However, other people live until nearly 100 years of age, and more. Is that fair? Why didn't God give those two people an equal opportunity? He can easily extend the lives of all human beings so that they live the maximum amount of time in order to make the all important decision of turning to Jesus.
3) (This question is aimed at synergists who believe one can lose his/her salvation) Since God is in control of when we live or die, if you can lose your salvation, why doesn't God kill you during the time you are in the "saved state"? Isn't He doing everything he can do to keep you out of hell?
4) Speaking of fairness, if God desperately wishes everyone would be saved, why does He allow such diverse situations in the human race? For example, some Americans are born in the Bible belt where there is a church on every corner, access to TV channels where the gospel is proclaimed, access to people in their neighbourhoods and schools and work places who are Christians, for the possibility of interacting with those Christians and receiving the gospel message or seeing the Lord work the lives of those people as a powerful testimony to the fact that God does indeed change lives.
Other people are born in remote jungle tribes who have no idea who Jesus is, no access to missionaries, no TV channels, etc. The American person in our example lives a comfortable life so he has plenty of time to sit and ponder whether there is truth to the Bible's claims. The other person in the jungle doesn't even know what the Bible is, much less have time to sit around pondering such things, as he is more concerned with surviving and drinking fresh water. In fact, if he came across a Bible, it might not even be in his language.
Is that fair? Did God truly give the same chance and opportunity to these two people?
Ask any missionary and they will tell you there are huge amounts of people groups that have never heard the name of Jesus. Not only in uncivilized parts of the world, but in civilized parts, too.
In some countries, Christianity is illegal. Do Chinese people have the same chance as Americans? Americans can go to a Christian church freely to ask questions about Jesus and ponder eternal, spiritual things. Certain countries in Asia, not so much. Is that really equal and fair?
5) More on fairness: Both angels and humans are guilty for sin. God provided a salvation plan for humans, but none for angels. There is no plan of redemption for fallen angels.
Is that fair?