Both were more practice than theory. Both had certain value preferences. This value preference was stability and strength as systems. Both had preference for restraints.
Roman constitutionalism is known to us through polibious. The Roman constitutional according to Polibious consisted of—Rules supported by laws which in turn were supported by Religion.
In the Medieval period, the role of Church is important. Church restricts the monarch from becoming a tyrant.
According to Christiandom ‘only those laws are good which have their base in religion.’ Political thinkers followed the trend set by St. Augustine and St. Thomas in making secular authority subsequent to the authority of the Church.
This baleful mate of affairs could not be remedied until after a period of about 800 years. The national monarchs raised their heads to overthrow the discredited hold of the papacy.
2. Liberal Theory:
Hobbes rejected the idea of constitutionalism. He was in favour of unrestricted power in the hand of Leviathan. Thomas Harrington was in favour of government of laws. He was against government of men.
Locke favored constitutionalism, limited government, people have right to give themselves a constitution. He talks about natural rights. It restricts the government. He was in favour of division of law making power. This was an attempt to put restriction.
Western writers like Thomas Saine, James Bryce, Harold J. Laski, Herman Rines, Charles H. Mcliawain, C.F. Strong, Carl J. Friedrich etc. have taken a view that constitutionalism is both an end and a means; it is both value free and value ladden, it has normative and empirical dimension.
Whether the constitution is in the form of a document made at a particular time of history as the American constitution was made by the Philadelphia Convention in 1787, or it is in the form of numerous laws, institutions, and conventions.
Western concept of constitutionalism lays stress on this point that the basic laws of the land should be such that the difference between the government of the people and the constitution of the state is discernible. The constitution is more important than the government.
The western concept of constitutionalism desires a constitutional state with a well acknowledged body of laws and conventions. It has a legislature, an executive, and judiciary, all required to work within the prescribed framework by following the defined procedure.
If there is a change, it should be peaceful and orderly so that the political system is not subjected to violent stresses and strains.
There is the rule of law ensuring liberty and equality to all; there is the freedom of the press to act as the Fourth estate, there is a plural society having freedom for all interests to seek the corridors of power, there is a system that strives to promote international peace, security and justice.
3. Marxist Theory:
The Marxists begin their theory by criticizing liberal theory. According to them liberal constitutional theory is status quoits. Socialist constitutionalism aims at socialist transformation.
The constitutionalism is not an end in itself; it is just a means to implement the ideology of scientific socialism. It is a tool in the hands of the dictatorship of the proletariat that seeks to establish classless society that would eventually turn into a stateless condition of life.
The purpose of having the constitution is not to limit the powers of the government but to make them so vast and comprehensive that the ideal of workers state is realized and a new type of state comes into being.
The real aim of the constitution in such a country is not to ensure liberty and equality, rights and justice for all but to see that the enemies of socialism are destroyed and the new system is firmly consolidated.
The Marxist concept of constitutionalism is based on the principles of a particular ideology of Marxism-Leninism according to which the state is viewed as a class institution whose raison is to act as an instrument of exploitation and oppression by one class over another. What the constitution of the state but the policy of communist party is supreme. State and thus constitutionalism is seen to have class character. It incorporates rights.