Exodus 30:34-37

The LORD said to Moses: Take sweet spices, stacte, and onycha, and galbanum, sweet spices with pure frankincense (an equal part of each), and make an incense blended as by the perfumer, seasoned with salt, pure and holy; and you shall beat some of it into powder, and put part of it before the covenant in the tent of meeting where I shall meet with you; it shall be for you most holy. When you make incense according to this composition, you shall not make it for yourselves; it shall be regarded by you as holy to the LORD.