  The renormalization of the two dimensional light-front quantized $\phi^{4}$
theory is discussed. The mass renormalization condition and the renormalized
constraint equation are shown to contain all the information to describe the
phase transition in the theory, which is found to be of the second order in
agreement with the conjecture of Simons and Griffith. We argue that the same
result is also be obtained in the conventional equal-time formulation.
