זוהר שמות — דף ריח ע”ב

One who has a good eye blesses with joy and this nourishes the place that has nothing on its own. The birkat hamazon with joy and goodwill prepares a place in the holy palaces. The tsits on the high priest's forehead atoned for the shameless: the letters of the holy Name shone before the ashamed and broke their heart. The ketoret breaks the evil inclination from all sides. Blessed is one who keeps the commandments and knows their secret, for each mitzvah contains supernal secrets and lights.