"Surely the humanism that prevails our culture is not equipped to answer such grim displays of evil through the actions of people as Seung-Hui. The psychologist, likewise, may attack outside influences in trying to nail down precisely what was troubling him, however, the answer as to “why” remains elusive. Many post-modern university professors may have a hard time even deciding whether or not this was evil or not. Regardless of who is asked we seem to get a similar response, something was wrong with him. For most assuredly, something has to be wrong in order to make someone do such unspeakable things."
"Additionally, it is a good time for the Christian to compassionately speak out against evil and to promote the God who alone has triumphed over it, will not turn a blind eye to it, and will one day completely eradicate the earth from it. We understand that history is moving in a linear direction, towards its pinnacle point, the return of the Lord Jesus Christ to rule and reign with all evil firmly suppressed under his sovereign foot. There is a day coming when he will reign in righteousness and all who do not submit to him will be crushed."The Desiring God Blog seeks "What's at the Heart of the Murders?" and describes how to minister to the suffering. Here is also another article that answers why (although it was written in response to 9/11.)
"The Bible is overwhelmingly clear that God governs everything in the universe from the smallest bird to the largest storm. “Are not two sparrows sold for a penny?And not one of them will fall to the ground apart from your Father” (Matthew 10:29). “Even winds and sea obey him” (Matthew 8:27). “The lot is cast into the lap, but its every decision is from the Lord” (Proverbs 16:33). “The king’s heart is a stream of water in the hand of the Lord; he turns it wherever he will” (Proverbs 21:1). “Who has spoken and it came to pass, unless the Lord has commanded it?” (Lamentations 3:37). “Does disaster come to a city, unless the Lord has done it?” (Amos 3:6). “He commands even the unclean spirits, and they obey him” (Mark 1:27). “I am God, and there is none like me . . . saying, ‘My counsel shall stand, and I will accomplish all my purpose’” (Isaiah 46:9-10).
There is no person or being in the universe that can thwart the sovereign will of God. Satan is his most powerful enemy and does much evil in the world, but he must first get God’s permission, and none of his actions is outside God’s governance. He never breaks free from his leash (Luke 22:31; Job 2:6-7; 42:11)."