The phrase "unsparing of self" refers to someone who is completely dedicated and selfless in their actions. They put the needs of others before their own and are willing to sacrifice their time and energy in order to achieve their goals. Synonyms for this phrase include "self-sacrificing," "unselfish," "devoted," "altruistic," and "generous." Each of these terms emphasizes the idea of giving of oneself without expecting anything in return. They convey a sense of nobility and virtue, highlighting the admirable qualities of those who embody these characteristics. Those who are unsparing of self often inspire others to follow their example and make a positive impact on the world around them.