Definition. A miracle is a special act of God that interrupts the natural course of events. The Christian conception of the miraculous immediately depends on the existence of a theistic God. If the theistic God exists, miracles are possible. If there is a God who can act, then there can be acts of God. The only way to show that miracles are impossible is to disprove the existence of God.

The above statement immediately calls for clarification: what are "special acts" of God? How are they known when they occur? There must be specific distinguishing characteristics of miracles before one can analyze events that possess these characteristics. Simply to say a miracle is a singularity is insufficient. Singularities occur in nature without obvious divine intervention.

Theists define miracles in either a weak sense or a strong sense. Following Augustine, the weaker definition describes a miracle as "a portent [which] is not contrary to nature, but contrary to our knowledge of nature" (Augustine, 21.8).

Others, following Thomas Aquinas, define a miracle in the strong sense of an event that is outside nature’s power, something only done through supernatural power. This latter, stronger sense is important to apologists. A miracle is a divine intervention, a supernatural exception to the regular course of the natural world, Atheist Antony Flew put it well: "A miracle is something which would never have happened had nature, as it were, been left to its own devices" (Flew, 346). Natural laws describe naturally caused regularities; a miracle is a supernaturally caused singularity.

To expand on this definition, we need some understanding of what is meant by natural law. Broadly, a natural law is a general description of the usual orderly way in which the world operates. It follows, then, that a miracle is an unusual, irregular, specific way in which God acts within the world.

Probability of Miracles. Whether we can know if miracles actually happened depends on answers to three questions: (1) "are miracles possible?" (2) "are New Testament documents reliable?" (3) "were the New Testament witnesses reliable?"

An often overlooked argument is that for the probability of miracles. It is true that philosophy (i.e., arguments for God’s existence) shows miracles are possible but only history reveals whether they are actual. But it is also true that, granting existence of a theistic God, miracles are probable.

A theistic God has the ability to perform miracles since he is all-powerful or omnipotent. Second, he has the desire to perform miracles because he is all-knowing or omniscient and all-good or omnibenevolent. One who examines history to see whether God has performed any miracles already can know that God is the kind of God who would if he could, and he can.

Why would God perform miracles if he could? By nature and will he is the kind of God who desires to communicate with his creatures and do good for them. And a miracle by definition is an event that does this very thing. Miracles heal, restore, bring back life, communicate God’s will, vindicate his attributes, and many more things that are in accord with his nature. Such things befit the nature of the One performing them (the Creator and Redeemer) and the need of the one for whom they are performed (the creature). By analogy, what good earthly father who had the ability to rescue his drowning child would not do everything in his power to do so? And if he had all power, then we know in advance that his goodness would lead him to do so. How much more our heavenly Father? So we know in advance of looking at the evidence for the actuality of miracles that if God exists they are not only possible but probable.

Further, if a miracle is an act of God to confirm the word of God through a messenger of God, then it is reasonable that God would want to do miracles. Through miracles, God confirms his prophets (Heb. 2:3-4). This is the way God confirmed Moses (Exod. 4) and Elijah (1 Kings 18). And this is the way he confirmed Jesus (John 3:2; Acts 2:22). How better could God confirm to us who were his spokespersons. And it is a priori probably that an intelligent, personal, moral Creator would want to communicate in the most effective way with his creatures.

Reality of Miracles. While philosophy makes supernatural events possible and the nature of a theistic God shows they are probable, only history reveals whether they are actual. But "history" here includes both the history of the cosmos and the history of the human race.

The reality of miracles in human history is based on the reliability of the New Testament documents and the reliability of the New Testament witnesses. For given the trustworthiness of their combined testimony it is beyond reasonable dispute that the New Testament records numerous miraculous events.

Dimensions of Miracles. In the Bible’s pattern, a miracle has several dimensions:

First, miracles have an unusual character. It is an out-of-the-ordinary event in contrast to the regular pattern of events in the natural world. As a "wonder" it attracts attention by its uniqueness. A burning bush that is not consumed, fire from heaven, and a person strolling on water are not normal occurrences. Hence, they draw the interest of observers.

Second, miracles have a theological dimension. A miracle is an act of God that presupposes a God who acts. The view that a God beyond the universe created it, controls it, and can interfere in it is theism.

Third, miracles have a moral dimension. They bring glory to God by manifesting his moral character. Miracles are visible acts that reflect the invisible nature of God. No true miracle, then, is evil, because God is good. Miracles by nature aim to produce and/or promote good.

Fourth, miracles have a doctrinal dimension. Miracles in the Bible are connected directly or indirectly with "truth claims". They are ways to tell a true prophet from a false prophet (Deut. 18:22). They confirm the truth of God through the servant of God (Heb. 2:3-4). Message and miracle go hand-in-hand.

Fifth, miracles have a teleological dimension. Unlike magic, they are never performed to entertain (see Luke 23:8). Miracles have the distinctive purpose to glorify the Creator and to provide evidence for people to believe by accrediting the message of God through the prophet of God.

Theistic Context for a Miracle. An essential feature of biblical miracles is their theistic context. Only within a theistic worldview can a miracle be identified. When Moses came upon the burning bush (Exod. 3:1-6), he began to investigate it because of its unusual nature. The accompanying word from God told Moses that this event was not merely unusual, but a miracle. If Moses reported to convinced atheists what had happened at the burning bush, they would have been within their rights to doubt the story. In an atheistic universe it makes no sense to speak about acts of God. A burning bush and a voice would seem to the nontheist no more miraculous than the voice from heaven did to those who took it to be thunder (John 12:29), But granting that God exists and something about his rational and moral nature, these defining characteristics give miracles their apologetic power

Conclusion. We must know what we are looking for before we can recognize a miracle. First, miracles stand in contrast to nature, which is God’s regular and naturally predictable way of working in the world. Miracles are an unusual and humanly unpredictable way in which God sometimes intervenes in the events of the world. A miracle may look like any unusual occurrence, but it has a supernatural cause. It is performed with divine power, according to the divine mind, for a divine purpose, in order to authenticate a divine message or purpose.