Yesterday, I had a conversation with friends on the relationship between Calvin and 'Calvinist'. That led me to read up Richard A. Muller's lecture given at Calvin College in 2009 that addressed this question.
It is very interesting to find out from Muller, who is noted for his 4-volumes of Post-Reformation Reformed Dogmatics (USA: Baker Academic) and his two books on John Calvin (The Unaccommodated Calvin: Studies in the Foundation of a Theological Tradition and After Calvin: Studies in the Development of a Theological Tradition, both published by Oxford University Press), about the famous TULIP and how Calvin was not definite on "L", Limited Atonement (emphasis added):
It is really quite odd and a-historical to associate a particular document written in the Netherlands in 1618-19 with the whole of Calvinism and then to reduce its meaning to TULIP. Many of you here know that the word is actually "tulp." "Tulip" isn't Dutch--sometimes I wonder whether Arminius was just trying to correct someone's spelling when he was accused of omitting that "i" for irresistable grace. More seriously, there is no historical association between the acrostic TULIP and the Canons of Dort. As far as we know, both the acrostic and the associated usage of "five points of Calvinism" are of Anglo-American origin and do not date back before the nineteenth century. It is remarkable how quickly bad ideas catch on. When, therefore, the question of Calvin's relationship to Calvinism is reduced to this popular floral meditation--did Calvin teach TULIP?--any answer will be grounded on a misrepresentation. Calvin himself, certainly never thought of this model, but neither did later so-called Calvinists. Or, to make the point in another way, Calvin and his fellow Reformers held to doctrines that stand in clear continuity with the Canons of Dort, but neither Calvin nor his fellow Reformers, nor the authors of the Canons, would have reduced their confessional position to TULIP.
In fact, it is quite evident in the cases of "T" and the "L." I don't think Calvin ever uttered a phrase that easily translates as "total depravity." He certainly never spoke of "limited atonement." Neither term appears in the Canons of Dort, nor is either one of these terms characteristic of the language of Reformed or Calvinistic orthodoxy in the seventeenth century. (p.8)
Simply stated, neither Calvin, nor Beza, nor the Canons of Dort, nor any of the orthodox Reformed thinker of the sixteenth and seventeenth centuries mention limited atonement--and insofar as they did not mention it, they hardly could have taught the doctrine. [...] To make the point a bit less bluntly and with more attention to the historical materials, the question debated in the sixteenth and seventeenth centuries, concerned the meaning of those biblical passages in which Christ is said to have paid a ransom for all or God is said to will the salvation of all or of the whole world, given the large number of biblical passages that indicate a limitation of salvation to some, namely, to the elect or believers. This is an old question, belonging to the patristic and medieval church as well as to the early modern Reformed and, since the time of Peter Lombard, had been discussed in terms of the sufficiency and efficiency of Christ's satisfaction in relation to the universality of the preaching of redemption. (p.9)
Various of the later Reformed appealed to Calvin on both sides of the debate. [...] Later Reformed theology, then, is more specific on this particular point than Calvin had been--and arguably, his somewhat vague formulations point (or could be pointed) in several directions, as in fact can the formulae from the Synod of Dort. (p.10)
The whole lecture is made available by Calvin College here.
So what do you think about the relationship between John Calvin and TULIP? Should TULIP be the central identifier, the litmus test, for people to identify themselves as 'Calvinist'? Why, and why not?