Yes, as sure as I believe that I exist, and that existence itself is truth.
No one can run a test to prove the existence of God. Neither can you run a test that proves, using the scientific method, that God does not exist, not even atheists, not even the most respected and experienced team of scientists. The reason for this, from God's standpoint, is both clear and fair:
What many atheists call "evidence" is not the same as what makes them atheists. The reason for this is that people will usually accept what is in agreement with their own world view, and real evidence has no such bias.
This is true of pretty much every philosophical stance, so ultimately, no matter what evidence you or anyone presents, a person must make up their mind and heart.
There is great wisdom in this arrangement, because by our choices we reveal who we are, and that is what a super-intelligent God who gave us free will would want for us to reveal.
The question of whether God exists, ideally, is one which each person must make up in their own mind. If someone should claim that they have a test that, say, either proves or disproves the existence of God, then some authority will impose that legally on people and will penalize those who feel differently.
Roman Emperors Constantine and Theodosius tried to do exactly that, and as a result, many people lost their homes, their religious buildings were seized and converted into the emperors' version of the worship of God, and a lot of people were imprisoned.
On the other hand, over in Russia in the late 19th and early 20th centuries, the leaders tried to impose an atheistic philosophy, and those who disagreed were treated similarly, with lootings, property seizings, and imprisonments. In fact, that particular campaign hasn't completely ended even now.
As one who believes in one Almighty God and his Son and our Savior Jesus Christ, I am compelled to provide reasons to believe in God no matter how the political winds blow where one lives:
People believe in God because God makes himself known through his works. Also, because just like a house is constructed by someone, the one who constructed all things is God. Thirdly, a real, ultimate Creator, by definition, has to be uncreated, so there must be only one.
God reveals himself in many ways, and those who search for him honestly will find him. Just because a Creator of the universe cannot be seen does not deny his existence, because we don't see gravity, or the wind, or electricity, but we know that they exist, because we see their effects.
Similarly, when we see lives radically changing for the better because of a new found faith in a Creator, we are seeing the effects of God in their lives. I have seen this many, many times, and no atheist can deny that this happens.
Christians believe in the God of the Bible who recommends himself to be the Creator because of consistent fulfillment of prophecy. Secondly, particularly in the last hundred years or so, every few months a discovery in science or archaeology is made that corroborates some aspect of the Bible's account.
Third, the morality of the Bible's commands to Christians about how to live our lives works for everyone - respect for life, respect for property, respect for reproductive powers, respect for truth, and most of all, to put God's service in the center of our lives. This is due to the power of the holy spirit, which is God's power.
Christians also believe in the existence of God because the Bible teaches that he is a just and righteous God. This is why he sent his only begotten Son to us, in order that those who put faith in him can have everlasting life. He sent his Son into the world in order that the world can be saved through him. He gave his soul in behalf of humankind John 3:16-17; Matthew 20:28
There is a lot of evil in this world, that is, a lot of self-destructive, selfish, violent, senseless behavior, and this is a puzzle in the minds of many of the most dyed-in-the-wool evolutionist/atheists, because they would expect that all of these "millions and billions of years of evolution" would result in a more productive behavior pattern. But it is caused by the evil in many humans, and because, right now, Satan is the ruler and god of this world. John 14:30; 2 Corinthians 4:3-4 God our Creator, because he is a just God, has a plan to get rid of the evil in the world, and undo the evil that has been done.
Think about that: Why don't people love one another, without God? Why is there war and crime and hunger in a world of plenty and lots of scientific discovery? It is not about the man made aspects of some religions, it is about man needing God to guide their roadway. They are doing a pretty bad job of it now.
Fear of punishment, and faith in that punishment does not lead a believer in God to do right. God is not a slave driver, making you do what you don't want to do. If it is in your heart to want truth and righteousness and love, you will be drawn to the true God.
The idea that people who believe in the existence of an intelligent Creator have the burden of proof skews the argument in favor of atheists, because they feel that they don't have to prove their position - they just state it. However, the very fact that the universe is here with characteristics that cannot be brought about by chance is sufficient proof that a long living, goal oriented, personal intelligence is the cause.
The truth is that there is no proof that there is no intelligent Creator - and the tremendous complexity and interconnectedness of our existence strongly indicate that one does. Atheists generally do not want to talk about beginnings or of finding final answers to important questions, which is the whole point of it all. Who am I? What am I? Where did I come from? Where am I going? Is this life all there is? We could give our opinion about these questions, but opinions are not answers.
There is nothing unreasonable about these facts. There are some suppositions and hypotheses out there that have no real basis, but these facts remain. Therefore, a scientist can believe that the universe was created by an intelligent being outside of time and space, without denying science.
Regarding morality: atheists sometimes point to people who are atheists and who are moral, in their estimation. It should also be noted that atheism does not make them moral. There are atheists who are very amoral but who are still atheists. If a Christian is amoral, they are acting against the teaching that they apparently accepted at some point. Jesus himself said repeatedly that if someone comes to him saying "Lord,Lord" but does not do the will of his Father, he will reject them. Matthew 7:21; Luke 6:46
So we have incentive to do better morally in our lives, by our acceptance and love for our Creator, and by the example set by Jesus Christ.
It is true that most great scientists in history believed that the earth was created.
But to insist that scientific methodology was conceived only in the last 300 years is unreasonable, especially in view of our knowledge of ancient cultures and their accomplishments - they were not all ignorant deluded illiterate goat herders.
It is also true that the modern scientist accepts that at some point in the distant past, the universe began to exist.
This fact brings Kalam's Cosmological Argument into play. (Google it)
It is also true that an alternate cause of the universe is intelligent rather than a mindless force. The question then is, is the ultimate source of that existence someTHING or someONE -- that is, a mindless random source, or an intelligent one?
Because information has never resulted from randomness, the intelligent answer is superior.
Therefore, there exists an intelligent, uncreated Creator of the universe. There is only one Creator, and if you search for him, he will let himself be found by you, and he is not far off from each one of us.