The expression "shall come a time" can be replaced by various synonyms that slightly modify the meaning of the phrase. For instance, "there will come a moment" implies a specific point in time, while "eventually" suggests a more indefinite period. Other synonyms to consider include "ultimately," "in due course," "sooner or later," and "one day." All these expressions convey the idea that a particular event or circumstance is inevitable, but differ in the sense of urgency that they imply. Therefore, selecting the appropriate synonym will depend on the context and the degree of importance one wishes to give to the impending moment.