What people call sacrifice (sattrâyana), that is really abstinence, for by abstinence he obtains from the Sat (the true), the safety (trâna) of the Self. What people call the vow of silence (mauna), that is really abstinence, for he who by abstinence has found out the Self, meditates (manute).

In plain words: Long sacrifices and the vow of silence are also really self-discipline. By disciplined living a person finds safety in the True, and one who has found the Self through it truly meditates.