Kitab-i-Aqdas/Elder46

There is no harm in using vessels of gold and silver [note 2] if one desires to do so. Beware of dipping your hands in large plates (al-sihaf) and basins (al-suhun). [note 3] Hold to what is closer to cleanliness. [note 4] He desires to show you the customs of the people of Paradise (ahl al-ridwan) in His Impregnable, Unapproachable Kingdom.

Hold fast to cleanliness in all circumstances, lest the eyes fall on that which you and the people of Paradise abhor. Whoever transgresses (the rule of cleanliness), his work at once becomes futile.

If he has an excuse, God exempts him for He is the Generous, the Powerful.