Q. How does the “problem of evil” resolve itself in the Christian faith?  If God created everything, does that mean He also created evil?

When God created the heavens and the earth, everything He made was good (Genesis 1:31).  There was no trace of evil – no shortcoming in anything God had made.

Our first parents, Adam and Eve, enjoyed uninhibited communion with God in the garden He had given to them.  They loved Him of their own volition, and obeyed Him freely.  The Bible does not define exactly how long this continued, but at some point, evil entered this world through the lie of the serpent (Satan) to Eve.  By placing doubt into her mind as to whether God really meant what He said, he convinced her that she would be like God if she were to disobey Him.  She believed him, and ate of the only fruit in the garden which God strictly forbade.  Adam, being at her side, failed to protect her in her moment of temptation, and ate the fruit as well.  At this moment, Genesis tells us “their eyes were opened,” and they made coverings to hide their bodies (Genesis 3:7).

At the heart of the “problem of evil” is the element of human freedom.*  The Bible speaks often about role of human choice in believing and obeying him (Romans 1:18-23), and emphasizes the need for us to make a decision about whether we will follow him.  An objection which is often leveled against Christianity is that God is a cosmic tyrant who says “you do it my way, or no way at all.”  In reality, God has always given us two options: His or our own.  C. S. Lewis wrote that there are two types of people: There are those who kneel before God and say “thy will be done,” and those who refuse to bend their knee to Him, to whom God then says, “very well.  Thy will be done.”  Freedom to choose is a mark of humanness. As God chose to love us before we were born, so we, being made in His image and likeness, also have the choice to love Him. But He will not coerce us, and this is evidenced in the fact that even our first parents had the choice to believe God, or to believe the lie.

The answer then, is that God created everything, including human freedom, and humanity chose to abuse this gift.  Thus He did not create evil, and He is not responsible for evil.  Evil is the result of human beings abusing the gift of free will. And free will, though it carries the capacity to be used for evil, is also the only way in which true love can exist.  If we did not have the freedom to choose evil, then neither would we have the freedom of choosing to truly love.
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*As an aside, “the problem of evil” is often used as an attack on faith.  However, evil is an even bigger problem for the atheist than it is for the Christian.  When we posit that there is real evil, we also assume that there is real good.  But this distinction requires a real, objective moral law on the basis of which to differentiate between good and evil.  This moral law must have a source, and that source is God, as it is absurd to think that humanity would ever develope such a universal, innate moral compass by chance.  Thus the problem of evil does more to bolster the claim for God than to dispel it.

Q. Is there an absolute proof of Gods existence or does it completely come down to faith and personal testimony? Romans 1:20 For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, his eternal power and Godhead; so that they are without excuse. Invisible meaning actually can’t physically be seen, but at the end says are clearly seen by the world around us.
Let’s focus first on the verse quoted above: Romans 1:20.  In it Paul is talking about the material manifestations of God’s eternal attributes.  In other words, he says that something of who God is can be seen in the things that He has made; that the creation bears the image of its creator.  This refers not only to the planet we live on, but also to the inner-workings of we as human beings.
Only Two Ways To Look At Things
Essentially, there can be only two reactions to Paul’s point.  Either we infer a great creative mind from the incomprehensible complexity and beauty we behold in creation, or, we believe that everything (and I stress, everything) we know of life is the result of one huge cosmic accident. This latter option would declare that everything from DNA, to romantic love, to art, to iPods, to earthworms, to irony, to Bach’s cello pieces, to dirt, to college degrees, to self-esteem are all products of the same cataclysmic explosion that happened somewhere in the ancient past, long before the laws of physics (the ones we use to describe it) had come into existence.

This reductio ad absurdum, though it shows the irrational grounds of materialistic evolution, does not prove the existence of God outright.  What it does help us to do is make an inference to the best possible explanation, which is that all the complexity of life, emotion, physics, energy, and thought owe their existence to a Being more complex and wise than a cosmic cocktail of chemicals (which, by the way, would have had to come from somewhere).*
Absolute Proof
In the end, the answer to the question is that there is BOTH absolute proof and the assurance of faith and personal testimony.  Aside from any arguments related to the creation/evolution debate, we have absolute proof for God of another kind: the life of the historical Jesus. Even if God had left no visible traces of His divine nature in creation, as Paul wrote, we would still be left with the record of the God-Man himself.

The evidences from the life of Jesus form a greater proof for God’s existence than all the volumes of arguments written on God’s existence as proved from material creation.  And this is to be expected, because the focus of the Bible is not the scientific evidence we have for belief in God; it is rather the eternal Word of God, manifest in the God-Man Jesus Christ, whose life is the greatest proof for God available to us.

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* Proceeding with an argument for God’s existence from design would take a much longer than the scope of this post.  Serious inquirers would be well served to obtain a copy of documentaries such as “The Privileged Planet,” or books such as I Don’t Have Enough Faith to be an Atheist by Norman Geisler.