The word "wast a source of strength" does not have direct antonyms. However, there are words that can be used to convey the opposite meanings. For instance, the antonyms of "wast" are "saved," "preserved," or "conserved." By contrast, the antonym of "strength" is "weakness," "fragility," or "feebleness." Therefore, when looking for the antonyms of "wast a source of strength," one can replace it with phrases like "saved a source of weakness," "preserved a source of fragility," or "conserved a source of feebleness." These antonyms convey the opposite meaning of wast a source of strength, which refers to something that provides energy, support, or encouragement.