The Greek word translated "compassion" in the New Testament is splanchnizomai — from splanchna, meaning the bowels, the gut, the innermost organs. When Jesus saw the crowds and had compassion, it was a visceral response, not an intellectual one. He was moved in his depths. This word is used to describe Jesus in Matthew and Mark more than any other emotional term. Compassion is not a peripheral quality of his character; it is close to the center.
The parable of the good Samaritan is often read as a lesson in helping neighbors. It is also a lesson in who was qualified to be compassionate. A priest passed. A Levite passed. The man who stopped was a Samaritan — ethnically despised, religiously suspect, someone who had every social reason to keep moving. Compassion in this parable crosses every line that typically keeps people apart.
Paul's language in Colossians 3:12 is telling: "Put on therefore, as the elect of God, holy and beloved, bowels of mercies, kindness, humbleness of mind, meekness, longsuffering." Bowels of mercies — splanchna oiktirmōn — is the same gut-level word. He is describing compassion as something you put on deliberately, like clothing. It doesn't always arise naturally. Sometimes you choose to extend it before you feel it.
Commentary is from a charismatic Protestant perspective, drawing on KJV text and public-domain sources including Spurgeon, Andrew Murray, and Matthew Henry.