The phrase "be carnal" refers to indulging in physical or sensual pleasures. Antonyms for this phrase can include "abstain" or "restrain," which suggest abstaining from or controlling physical desires. "Spiritual," "virtuous," and "chaste" may also be considered antonyms, indicating a focus on spiritual or moral values rather than physical desires. "Sublime," "ethereal," and "transcendent" may also be used as antonyms, denoting a focus on higher, intangible goals rather than carnal pleasures. Ultimately, the choice of antonym will depend on the specific context and the intended connotations of the writer or speaker.