Plutarch, De Iside et Osiride
Frank Cole Babbitt, Ed.

If, as I have promised,¹ I must now speak of the offerings of incense which are made each day, one should first consider that this people always lays the very greatest stress upon those practices which are conducive to health. Especially in their sacred services and holy living and strict regimen the element of health is no less important than that of piety. For they did not deem it proper to serve that which is pure and in all ways unblemished and unpolluted with either bodies or souls that were unhealthy and diseased.² Since, then, the air, of which we make the greatest use and in which we exist, has not always the same consistency and composition, but in the night-time becomes dense and oppresses the body and brings the soul into depression and solicitude, as if it had become befogged and heavy, therefore, immediately upon arising, they burn resin on their altars, revivifying and purifying the air by its dissemination, and fanning into fresh life the languished spirit innate in the body, inasmuch as the odour of resin contains something forceful and stimulating.

Again at midday, when they perceive that the sun is forcibly attracting a copious and heavy exhalation from the earth and is combining this with the air, they burn myrrh on the altars ; for the heat dissolves and scatters the murky and turgid concretions in the surrounding atmosphere. In fact, physicians seem to [p. 187] bring relief to pestilential affections by making a large blazing fire, for this rarefies the air. But the rarefication is more effective if they burn fragrant woods, such as that of the cypress, the juniper, and the pine. At any rate, they say that Acron, the physician in Athens at the time of the great plague, won great repute by prescribing the lighting of a fire beside the sick, and thereby he helped not a few. Aristotle³ says that fragrant exhalations from perfumes and flowers and meadows are no less conducive to health than to pleasure, inasmuch as by their warmth and lightness they gently relax the brain, which is by nature cold and frigid. If it is true that among the Egyptians they call myrrh ‘bal,’ and that this being interpreted has the particular meaning ‘the dissipation of repletion,’ then this adds some testimony to our account of the reason for its use.