How to say "devout" in Japanese

• 信仰深いしんこうぶかい
  i-adjectiveCovers 'devout' in its plain sense: it says, literally, that a person's religious faith is deep. Think of a believer whose daily life plainly reflects that faith.
• 敬虔けいけん
  na-adjective, nounIts primary sense is 'pious' — reverent devotion rather than sheer depth of faith — so it fits contexts where piety itself is the point; for plainly calling someone devout, the other two are more direct.
  いかにも敬虔けいけんなるクリスチャンが送おくる、礼節れいせつ重おもき言葉ことばです。↗

  So characteristic of what a pious Christian would say, this courteous phrase.
• 信心深いしんじんぶかい
  i-adjectiveThe broadest of the three, covering 'deeply religious', 'godly' and 'faithful' as well as 'devout'. It describes a person of deep, sincere faith and is close in meaning to 信仰深い.
  インカ人にんは信心しんじん深ふかい民族みんぞくだった。↗

  The Inca were religious people.

All three describe deep religious faith: 「信心深い」 is the broadest and a safe default for a devout person, 「信仰深い」 is a close synonym centred on depth of faith, and 敬虔 really means 'pious'.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 信仰深いしんこうぶかいdevout
• 敬虔けいけんpious
• 信心深いしんじんぶかいdeeply religious