Why did God make people if he knew they would sin?

以下是網路資料 – 但回答的好像不錯
重點翻譯一二：
一、先以父母與子女的關係作類比解釋
1.如同父母，不會因子女有可能成壞人而不生小孩。
2.有了小孩，可讓父母表現愛的天性。
3.既使小孩有是可能成為壞人，並不意味小孩不該來到世上。
4.小孩即使成為壞人，那也是他們自行的選擇
二、再回到神的觀點
1.神愛眾生，神由犧牲他的肉體(Jesus)表現大愛
2.正因為有罪惡，才讓大愛(犧牲)更能彰顯；因此神有意的允許罪惡的存在。
3.藉由罪惡 ==> 神的犧牲 ==> 使神的神聖，正義終將打敗惡魔，及神將庇護眾生等得以彰顯，也使神的地位更加榮耀。
三、結論
神即使知道，人會犯錯，也不影響神造世界(人)之意旨。且正因有了壞人，製造了受害者，但神使這些受害者終將得到庇護。
This is a simple question and we are tempted to answer it simply by saying, "Why not? Why shouldn't God make people if He knows they are going to sin?" But, such an answer isn't very . We could always say we don't know why God would do this since He is infinite
and we are not and His ways are not our ways. But this answer also leaves us a bit empty. So, let's see if we can answer the question by analogy.
When parents have children they know that their kids will eventually act in sinful and even harmful ways. Yet, that doesn't stop them from having children. Why? First of all, it is worth the risk of their rebellion to bring them into the world.
Second, the nature of love is to give and by having children the parents can better express their love.
Third, just because the children will sin and rebel doesn't mean they shouldn't exist.
Fourth, children have their own wills and can freely choose to rebel. Knowing this parents all over the world still have children. As you can see, analogies help us to make sense of thing, but they can't answer every question. That is why we must go to God's word for more insight.

The Bible tells us that God is love and that He sacrificed His Son on our behalf. The greatest act of love is to sacrifice one's own life for another (John 15:13). In a very real sense, God has performed the greatest act of love in sacrificing Himself (Remember, Jesus is God in flesh - John 1:1,14). Since God is love and love sacrifices, God has now manifested the greatest love by dying for us. In this, God is glorified. But, without sin in the world, there would be no way to demonstrate the greatest act of love -- which is self sacrifice. So, perhaps God allowed sin in the world so that He could demonstrate the greatest act of love.

Furthermore, in this self sacrifice God demonstrates the perfection of His holiness, the sinfulness of sin, the proof of God's righteousness, the victory over the evil one, and the guarantee of the saved with whom He can shed His love and glory forever. In this, God is glorified.
We could come up with a variety of possible reasons why God made
people knowing they would sin and we probably can never fully answer it. But, knowing that they would sin is no reason that God shouldn't make them, especially if His plan includes the acts of sinners so that others would be redeemed.