Punishing him was intended as a warning to others.
Tips
usage
儆 is a literary/formal character rarely seen alone. It most commonly appears in the idiom 以儆效尤 ('to punish one as a warning to others'), and in 儆戒, meaning 'to warn; to admonish'.
亻 is left-side 人 and frames 儆 as a human action - warning, cautioning, alerting. Same radical fronts 仪, 信, 仙 and most other person-acts-on-person verbs.
敬 supplies the sound, drifting from jìng to jǐng (tone shift). There may be a faint semantic echo - to warn is to instill respectful caution - but the main job is phonetic. 儆 often appears in 杀一儆百 (kill one to warn a hundred).
