The discussion on the moral issue in Mozambique starts from philosophical questions whose answer always implies the need for diagnosis and "cure" of a social evil. Questions are rarely asked about how morality, specifically justice as a "moral value", is constructed from the "social fabric" itself. Two questions arise: how do social actors define what is "fair" and "unfair", "good" and "bad"? How is justice politically conceived in different political contexts (and temporalities) that determined different forms of power relations in the history of Mozambique? Such questions place us in the field of Sociology of Morality. And, perhaps for this reason, there has been little interest from philosophers, leaving some void in the approach to the moral issue. This article aims to problematize the construction of this void. From an analysis of official documents, and based on Discourse Analysis focusing on the category "justice" as a moral value, it appears that the dynamics and form of morality in Mozambique as a recent country, occurs from of two differentials in political power relations, namely: openness to the constitution of a revolutionary bias and openness to a democracy with a liberal bias. Having noted these forms and dynamics, it is considered that a sociology of morality in the country would have to account for the contexts in which the moral issue is determined and the conditions under which it is possible. The concern of this sociology cannot be about what "should be". Furthermore, this "must be" also becomes the object of sociological investigation [ABSTRACT FROM AUTHOR]