As your day progresses, as one enters the field of daily work and toil, you are infused with the passionate quality (rajoguna). Before you take your lunch, meditate on the Lord again and dedicate the work, and the fruit derived from it to the Lord Himself. Start eating only after this act of devotion and grateful remembrance. This is the meaning of the noon (maadhyannika) worship. By observing this ritual, passion is kept in check and is overpowered by the satwic nature. During the day, people are possessed by a third nature, tamas or dullness. When evening descends, one hurries home, eats one’s fill, and is overpowered by sleep. But a duty still remains. To eat and sleep is the fate of idlers and drones. When the worst of the qualities, tamas threatens to rule, one must make a special effort to escape its coils by resorting to prayer in the company of those who extol the Lord, reading about the glory of God, the cultivation of good virtues, and the purposeful nursing of good rules of conduct. This is the prescribed evening worship (sandhyavandana).

- Dharma Vahini, Ch 7.