Inner component
辟 supplies an exact phonetic match: bì → bì, no drift.
辟 itself originally pictured a king pronouncing punishment (
尸 over
口 over
辛). Faint semantic resonance: opening a path, clearing the way - a command to step aside, mirroring
避's 'evade, give way'. Same phonetic gives
璧 (jade disc),
壁 (wall),
臂 (arm).