身 draws a standing person in profile with the torso swollen forward — most scholars read it as a pregnant figure: the body at its most bodily. The self you carry everywhere.
身 is body and self at once: 身体 (body/health — 身体好吗? asks after both), 身高 (height), 本身 (itself). 身份证 is the ID card — identity as 'body-status'. Confucian self-cultivation is 修身 — polishing the self like a craftsman polishes jade. And when something happens to you personally, it happens 亲身 — 'with one's own body'. In Chinese, you don't just have a body; you are one.
A person in profile, torso forward — the BODY you are.
身体好吗? 'is the body good?' is the standard health inquiry — Chinese asks after your body, not your 'health'.