It is not that simplistic, but then again it is not over complicated.
Imagine that I take a wetting agent, and apply it to 20% of these planks of wood. The "wetting agent" allows fluid to soak into the wood. I likewise, take the remaining 80% of wood and soak them in rain-x ... which makes them shed all fluid like water off a duck's back.
So in review I have made some intruments that are receptive to water and others that are not receptive ... in fact they repel water.
When I take each of these and dunk them, the water does not change what they are ... the water reveals some to be receptive and some to not be receptive.
LIKEWISE, there are those that are willing to say that Jesus is the Lord, and there are those that are not willing to say Jesus is the Lord. The reason for that is how they were fashioned so that in all things God gets the glory.
Your response to the Gospel does not change what you are. It reaveals what you are. It reveals how receptive and willing God has made you. In all things, the Creator gets the glory, and He does this through the free will that He gave you, and maintains for you.
Those that respond to the first utterence of the Gospel have nothing to boast about over those that have heard it a thousand times without any fruitfulness.
There is good soil that takes in the seed and produces a harvest, and there is bad soil, that the seed cannot penetrate. The SEED REVEALS the soil, it does not change the soil.
Do you understand?
So repent therefore, because all the dead in Christ and those still living in Christ, will be raised to life at the Last Day, receiving life everlasting. All the rest of the dead, who rejected Him or did not know Him, will also be raised and live at the end of the Millenial Kingdom. In that Day the penitent will receive life everlasting; and the wicked, condemnation forever separated from God. This is the second chance for those who will choose Christ and repent; or the second death for all those who will not accept the Truth nor will they repent of their evil deeds. So yes, fear Him who has given you life, because He can also take it away. ~ Timothy [Letters from God and His Christ - Volume 3 - The Word of God is Truth...Leading to Life]