Σπλαγχνίζομαι [5 verses](verb 1st sg pres ind mp) "Have compassion" is splagchnizomai, which means to "to feel great compassion." It is a New Testament word. It is from -splanchnon which means one's insides, inner organs, which were seen as the seat of feelings among the Greeks, the "chest" the higher feelings and the belly the lower. It is also is related to -splanchneuô, which means eating the inner organs of a sacrifice or prophesying from those inner.s organs. -  -  The Greek term that KJV translates as "I have compassion" is only used in the New Testament and only three times in Jesus's words. It doesn't exist elsewhere in Greek literature.  It is based on the general Greek term for the inner organs. It is connected to the idea that the inner organs are the seat of human feelings (something supported by recent research into the brain). The English terms "eating one's heart out" and having "gut feelings" or having one's "insides ache" carry a similar sensibility. There is also a religious side that has no parallel in English because the term is also linguistically related to the idea of eating the inner organs of an altar sacrifice.