For the religious life to be meaningful we must have free will, we must be able to choose between good and evil. If we do not have free will we cannot be held responsible for what we do.
According to Christians, God is all-knowing - he knows all the past, all the present and all the future. If this is so, then God must know everything we do long before we do it. This means that our whole life must be predetermined and that we act not according to the free exercise of our wills but according to our predetermined natures. If we are predetermined to be good we will be good and if we are predetermined to be evil we will be evil. We will act not according to our will or choice but according to the way God has already foreseen we will act. Although Christians will insist that we do have free will, God's omniscience simply makes this logically impossible. And that people will act only as God determines is verified in the Bible
If people are evil it is because God has chosen to make them evil (Rom 1:24-28) and caused them to disobey him (Rom 11:32). If they do not understand God's message it is because he has made their minds dull (Rom 11:8) and caused them to be stubborn (Rom 9:18). God prevents the Gospel from being preached in certain areas (Act 16:6-7) and he fixes long before it will happen when a person will be born and when he or she will die (Act 17:26). Those who were going to be saved were chosen by God before the beginning of time (ii Tim 1:9 Eph 1:11). If a person has faith and is thereby saved, their faith comes from God, not from any effort on their part (Eph 2:9-10). One may ask "If a person can only do what God predetermines them to do, how can God hold them responsible for their actions?" The Bible has an answer for this question.
But one of you will say to me: "If this is so, how can God find fault with anyone? For who can resist God's will?" But who are you, my friend, to answer God back? A clay pot does not ask the man who made it: "Why did you make me like this?" After all, the man who makes the pot has the right to use the clay as he wishes, and to make two pots from one lump of clay, one for special occasions and one for ordinary use. And the same is true of what God has done (Rom 9:19-22).
So apparently in Christianity a person's life and destiny are due purely to the whim of God and as mere humans we have no right to complain about what God has decided for us. The idea that we are all predetermined is quite consistent with the idea of an all-knowing God but it makes nonsense of the concept of making a' effort to do good or avoid evil.
Perhaps the most potent argument against the existence of an all-powerful, all loving God is the undeniable fact that there is so much pain and suffering in the world. If there is really a God of love who has unlimited power, why doesn't h put an end to all evil? Christians try to answer this question in several ways.
Firstly, they will say that evil is caused by man not God and that if only ma would follow God's commandments there would be no pain, evil or suffering. However, while it is true that evils such as war, rape, murder and exploitation ca be blamed on humans, they can hardly be blamed for the millions who die each year in earthquakes, floods, epidemics and accidents, all of which are natural; events. In fact, according to the Bible, the germs that cause hideous diseases like TB, polio, cholera, leprosy etc. and all the misery, deformity and suffering to which they give rise, were created by God before he created man (Gen. 1:11-12).
Another way Christians will try to explain away evil is to say that it is God's punishment for those who do not follow his commandments. However this implies that terrible things happen only to bad people, which is certainly not true. We often hear of painful sicknesses or disasters befalling good people including good Christians, and likewise we often hear of really bad people who seem to have nothing but good fortune and success. So it cannot be said that suffering and evil are God's way of punishing sinners.
Next, Christians will say that God allows evil to exist in the world because he wants to give us the freedom to choose good over evil and thereby earn salvation. Evil, they will say, exists to test us. At first this seems to be a good explanation. If a man sees someone being beaten up by a bully he has a choice between turning away (doing wrong) or deciding to help the victim (doing right). If he decides to help then he has been tested and found good. However, as we have seen before, an all-knowing God must already know what choices a person will make so what is the point of testing us? Also, even if suffering and evil exist in the world to test us, couldn't an all-loving God think of a less cruel and less painful way to do this? It seems unloving and unfair to allow pain to be inflicted on one person so that another person can have the opportunity to choose between good and evil.
Some Christians will try to free God from responsibility for evil by saying that it is not created by God but by the Devil. This may be true but again if God is so loving why doesn't he simply prevent the Devil from doing this? In any case, who created the Devil in the first place? Surely it was God.
By this stage the Christian will start to get a bit desperate, shifting the argument from logic to pragmatism. He will say that even though there is suffering in the world we can use it as an opportunity to develop courage and patience. This is undoubtedly true but it still does not explain why an all-loving God allows babies to die of cancer, innocent bystanders to be killed in accidents, and leprosy victims to suffer deformity and pain. In fact the existence of so much unnecessary pain, misery and evil in the world is very strong evidence that there is no all-loving all powerful God.
Christians claim that God is perfect, that he is complete in every way, but if God really did create the universe this would prove that he was not perfect. Let us examine why. Before God created the universe there was nothing - no sun, no earth, no people, no good or evil, no pain - nothing but God who was, according to Christians, perfect. So if God was perfect and nothing but perfection existed, what motivated God to create the universe and thus bring imperfection into being? Was it because he was bored and wanted something to do? Was it because he was lonely and wanted someone to pray to him?
Christians will say that God created everything because of his love of man, but this is impossible. God could not love humans before he created them any more than a woman could love her children before she had conceived them. God's need to create indicates that he was dissatisfied in some way and therefore not perfect. Christians might then say that God created spontaneously and without need or desire. However this would mean that the whole universe came into being without purpose or forethought and therefore it would mean that God was not a loving creator.
Christians claim that God wants us to believe in him so that we can be saved - but if this is so why doesn't God simply appear and perform a miracle so that everyone will see and believe? Christians will say that God wants us to believe in him out of faith, not because we see him with our eyes. However, according to the Bible, God in the past performed the most awesome miracles and often intervened dramatically in human affairs so that people would know his presence. So if he did so in the past, why doesn't he do so now?
Christians will say that God does perform miracles today (healing, solving personal problems etc) but being stubborn and evil most people refuse to believe. However these so-called miracles are individual and rninor and leave much room for doubt. If God performed a really impressive miracle which could have no other possible explanation, then most people certainly would believe.
According to the Bible when the Israelites wandered in the desert for forty years, God fed them by making food fall regularly from the sky (Ex16:4). During the 1980's, several million Ethiopian Christians died slowly and painfully from starvation due to a prolonged drought. God had then the opportunity to make food fall from the sky, as the Bible claims he did in the past, in order to prove his existence, his power and his love. Buddhists would say that God did not manifest his presence because he does not exist.