“To the law and to the testimony; if they speak not according to this word, it is because there is no light in them.” (Isaiah 8:20)
The Five Points of Calvinism (i.e., TULIP) are a logically consistent soteriological system. Beginning from the first point, Total Depravity, the subsequent points of Unconditional Election, Limited Atonement, Irresistible Grace, and Perseverance of the Saints seem to necessarily follow. It is this elegant and logical consistency that can be very intellectually satisfying, accounting for Calvinism’s power of attraction for many thinking believers. Logical consistency alone, however, is not the standard of truth. Rather, “[God’s] word is truth” (John 17:17), and it is against the absolute standard of “the law and the testimony” (Isaiah 8:20) that every claim must be measured.
The deviancy of Calvinism from the plumb line of Scripture begins with its understanding of Total Depravity. Scripture asserts that the unregenerate man is “dead in trespasses and sins” (Ephesians 2:1). Calvinists understand this assertion to mean that “the sinner is so spiritually bankrupt that he can do nothing pertaining to his salvation”; he cannot even respond to God by exercising the personal faith required for salvation (Acts 16:30-31) without first being sovereignly regenerated by God. From Paul’s use of the word “dead” in Ephesians 2:1, Calvinists construct the metaphor of the unregenerate man as a corpse (R. C. Sproul) or a cadaver (John F. MacArthur); since a literal corpse would not be able to respond to God in any way, the unregenerate man cannot either. Many Calvinists prefer the term Total Inability over Total Depravity to better express this concept, but based on their own analogy of corpse/cadaver the most accurate expression would be utter inability.
Metaphors (by definition) are partial, incomplete representations of reality; they inevitably break down when pressed too far. The Calvinist’s metaphorical construct of a physical corpse for the unregenerate man goes too far. For example, a physical corpse, in addition to being unable to believe, is also unable to sin, and yet the unregenerate man has no impediment to such an activity whatsoever. Scripture clearly presents a picture in which all men are commanded by God to believe in order to be saved (e.g., Isaiah 45:22; Mark 1:15; Acts 16:30-31), along with the implication that it is possible for unregenerate men to do so (e.g., John 3:16; 6:40; 7:37; 20:31; Revelation 22:17). The Calvinistic construct of the unregenerate man’s abilities/inabilities clearly lies beyond the true picture one sees in Scripture. Thus, although the subsequent four points may logically follow from the first, they suffer from an unbiblical understanding of Total Depravity that proves fatal for the system as a whole.
For additional analyses of Calvinistic teaching compared to Scripture, see:
 “The view one takes concerning salvation will be determined, to a large extent, by the view one takes concerning sin and its effects on human nature. It is not surprising, therefore, that the first article dealt with in the Calvinistic system is the biblical doctrine of total inability or total depravity.” David N. Steele and Curtis C. Thomas, The Five Points of Calvinism (Presbyterian & Reformed Publishing Company, Phillipsburg, NJ, 1963) 24.
 Steele and Thomas, The Five Points of Calvinism, 25.
 An axiom of Calvinism is that regeneration precedes faith.