To many atheists, the concept of thanking God is absurd, because in their mind, credit is due to man. A similar argument is that Christians should never be found in a hospital, but should instead pray for healing and good health.
Now, for a moment, we'll ignore the sovereignty of God in every matter. We'll forget the many verses that positively talk about the use of medical science and seeing doctors, even using this as an analogy for why we need to come to Christ. We will even pretend that Luke, a disciple who wrote a good portion of the New Testament, was, in fact a doctor. Let me ask just one simple question: Did you invent the seed?
Atheism was never a very well thought out belief system. Rather than thinking about the bigger picture, atheists spend so much time looking at the bits closest to the frame. The obvious answer to "did you invent the seed?" is no.
When it all comes down to it, even the atheist would be nowhere without God. Every human achievement is just a rearrangement of God's achievements. There is no absurdity thanking God for the harvest. Sure, we tilled the land, we planted the seeds, but did we invent the land? Did we invent the seeds? Did we control the weather conditions allowing them to grow? Did we invent the very bodies we use to do all these things? Did we give ourselves the intelligence to do all the things we do? The answer to all of this is no.
So, even taking out all the things such as God's sovereignty, we see that human achievement could not exist without God's achievements. The things we invent are a rearrangement of God's inventions. The very minds we use to do these brilliant things were given to us by God. Saying it's absurd to thank God because of humans is like me trying to take credit for the laptop upon which I write this article. I don't know the first thing about computers, I'm just using one to write this. You can thank Mark Zuckerberg for Facebook, you can thank Michael S. Dell for founding the company that made my computer, you can thank Charles Babbage for the initial invention of the computer, all of these men can thank God for the things they used for their achievements, right down to the circumstances that brought about their ideas.
So is it absurd to thank God? Far from it, it's absurd not to thank Him. We owe Him everything from our very existence to even our own greatest achievements. But it's not just this for which we can thank Him. We can thank Him for His love. See, we're not very grateful to God, as this article shows. When God created the first man, he had everything. A beautiful world in which to live, pure water to drink, a garden full of beautiful plants bearing food. He was naked without shame, as was his wife, and so clearly even the climate was ideal. And he had direct fellowship with God.
But he still wanted more, and so he and his wife took the one thing God said they couldn't have. In like fashion, every single one of us continues to rebel against God, and there is only one just punishment: Death.
But God's blessings did not end in Eden, for although we all deserve death, God tells us that He takes no pleasure in the death of the wicked, but prefers we repent and live. And so He, Himself, absorbed the cost of sin. 2,000 years ago, Jesus, the Son of God, came to live as a man, and unlike us He did not sin. Nevertheless, He died a sinner's death. By punishing Jesus in our stead, God made a way to reward us for Jesus' righteousness. All who confess Jesus as Lord, and believe God raised Him from the dead, will be saved.