These characters combine into two distinct but related concepts: 谦虚 (modesty) and 谨慎 (prudence). The four-character structure elevates the idea to a formal, respected virtue.
谦虚谨慎 is more than just a personality trait; it's a deeply ingrained cultural value in China, stemming largely from Confucianism. The ideal Confucian “gentleman” or “noble person” (君子, jūnzǐ) practices self-cultivation, and a key part of that is suppressing ego and acting with deliberation.
This term is formal and is most often used in writing or in serious, respectful conversations.