Incense offering in rabbinic literature

The incense offering (Hebrew: קְטֹרֶת, romanized: qəṭoreth), a blend of aromatic substances that exhale perfume during combustion, usually consisting of spices and gums burnt as an act of worship, occupied a prominent position in the sacrificial legislation of the ancient Hebrews. The correct blend of sweet spices and aromatic condiments used in making the incense offering was a carefully guarded secret at the time of its offering, fully known only by the compounders of the incense offering to prevent its replication in the worship of foreign gods.

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