Perhaps the simplest statement of it is the best: that it lies in a profound apprehension of God in His majesty, with the inevitably accompanying poignant realization of the exact nature of the relation sustained to Him by the creature as such, and particularly by the sinful creature. -The Works Of Benjamin B. Warfield; Volume V; Calvin and Calvinism, Part IV, Section 2, "Fundamental Principle", pg 354.In working man's English this means: When a man sees God in His radiant majesty, and then, looking back on himself, sees himself as a worm, Calvinism follows.
God and His glory is the guiding principle in Calvinism. Seeing God as the Holy, Exalted, Ruler, Sovereign, Merciful, Gracious, Awesome, Wrathful, Awful, and Loving God that He truly is, accompanied by a vision of who we truly are; vengeful, sinner, unholy, angry, hateful, full of lies and hypocrisy, it is only reasonable that we come to an understanding of salvation that rests solely and totally in God's sovereign mercies.
The first point of Calvinism is popularly called Total Depravity. But Total Depravity is not really the first point of Calvinism. God is the first point. God who created all things, God who works all things after the pleasure of His own will, God who causes all that is to continue to be.
Not only is God the first point of Calvinism, He is all the points of Calvinism! And yet, for ease of explanation, acronyms and points have been put together for our understanding.
Following the acronym TULIP then, Total Depravity comes first. This is a correct view of mankind when compared to God. When we say that mankind is 'depraved', we mean that mankind is morally corrupt and perverted. Corrupt means gone bad. Perverted means twisted.
As we look back at our initial creation, we find that God created us good and in His own image. But then we find that sin has twisted that image and corrupted it. Sin has taken those similarities we had with God, which were given to us by God, and turned them into something repulsive in the sight of God. Our morals were twisted, our desires were corrupted, and our wills were bound by sin.
On the other hand, when we see God through Scripture, we see Him revealed as Holy. He is revealed as all that man is not, can not be, and will not be. He is really and truly 'other'. He is not like us.
Isaiah saw God, and after he heard the angels singing back and forth to one another in an endless strain, "Holy, Holy, Holy is the Lord God Almighty, the whole earth is full of His glory!", his only response was this, "Woe is me. I am disintegrating. I cannot maintain myself in wholeness because I have seen God who is Wholly Other."
The guiding principle of Calvinism is God. Calvinists, like Isaiah, have caught just a small glimpse of the majesty and glory of God, and they cannot continue to see themselves in the same light as before. Now we must see ourselves by the light of the radiance of God's glory.