Strengthen
Part of speech: verb
Definition: To make strong or stronger; to add strength to; to increase the strength of; as, to strengthen a limb, a bridge, an army; to strengthen an obligation; to strengthen authority; to fortify; to reinforce. To animate; to give moral strength; to encourage; to fix in resolution; to hearten. To augment; to improve; to intensify. To grow strong or stronger.
Example sentence: He that wrestles with us strengthens our nerves and sharpens our skill. Our antagonist is our helper.
Fortify
Part of speech: verb
Definition: To increase the defenses of.To impart strength or vigor to.To increase the effectiveness of, as by additional ingredients.To strengthen mentally or morally.
Example sentence: Religion may have become a codification of morality, and it may fortify it, but it's not the origin of it.