Our Creator could have created beings devoid of free will, unable to choose wrongly, but that would have meant we would have been incapable of a genuine relationship with God. Suffering became a possibility when God created beings with free will, who were able to choose between right and wrong, with God warning: "Do not be deceived, God is not mocked; for whatever a man sows, that he will also reap" (Galatians 6:7). 

So much human anguish is the result of people making wrong choices that often also hurt others, but we also learn important lessons from these experiences. Warfare is the prime example of humanity reaping what we sow. Millions have been maimed and killed, even systematically murdered, in war. One of the darkest chapters in modern human history was the premeditated Nazi extermination of 6 million Jews in the Holocaust. 

The most active contributor to human suffering is an angelic being who rebelled against God and convinced a third of the angels to follow him (Revelation 12:4). God calls him an adversary (Satan) and a slandering accuser. He is also referred to as the "ruler of this world," the "prince of the power of the air" and "the god of this age" (John 12:31; Ephesians 2:2; 2 Corinthians 4:4).

Satan deceives mankind to follow him and reject God, as Paul explained to the Christians in Rome: "...the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be" (Romans 8:7). Without assistance from God, through the power of His Spirit, no human being is capable of correctly perceiving and effectively applying the principles of love and responsible behavior the Scriptures teach. Timothy describes God’s Spirit dwelling within us as "a spirit of power and of love and of self-discipline" (2 Timothy 1:7).

Bible prophecy teaches us to look forward to a time when Jesus Christ will return to earth to establish a godly world government that will enforce His righteous principles and change humanity's way of thinking. Then vast, sweeping changes will occur in God's relationship with all peoples on earth: "...many people shall come and say, 'Come, and let us go up to the mountain of the Lord, to the house of the God of Jacob; He will teach us His ways, and we shall walk in His paths.' For out of Zion shall go forth the law and the word of the Lord from Jerusalem" (Isaiah 2:3). During that time, most people will repent, surrender their lives to God and receive His Holy Spirit. 

A crucial aspect of developing godly character is to learn to love God and His ways above all else. And to do that we must learn, through personal experience, the sorrow and suffering that sin—rejecting God's ways—brings. God wants us to understand that every change we make in our lives in the direction of obeying His laws brings improvement into our lives, while every action that takes us further from His laws brings damaging consequences, often including suffering. God wants man to learn the lessons of where wrong choices and the wrong way of life lead—so we will loathe that way and never want to go there again.