The command to build the incense altar marks the climax of the Tabernacle's construction, introducing the element of scent into the sacred space. Standing within the inner sanctuary, this structure carries a profound spiritual weight, entirely distinct from the outer altar designated for animal sacrifices.
Although no animals are offered upon it, it is still called an altar. This is because its physical shape resembles an altar and it is used for holy service [קאסוטו], as well as the fact that on the Day of Atonement, the blood of sin offerings is placed upon its corners [הכתב והקבלה]. Its exclusive purpose is the burning of fragrant incense spices; it is never used for burnt offerings, meal offerings, or liquid libations [רשב״ם].
A central question arises regarding why the instructions for this altar appear at the very end of the Tabernacle commands, rather than alongside the other inner vessels like the Ark, the Table, and the Menorah. The primary approach among commentators explains this through the distinct purposes of the items. While the other vessels were designed to bring God's presence down to dwell among the Israelites, the incense altar serves to honor God after He has already rested His presence and willingly accepted the people's offerings. It is akin to presenting a sweet-smelling gift to a king within his throne room, serving as the ultimate, perfect seal that connects the physical and spiritual worlds [רמב״ן, ספורנו, צרור המור, בכור שור, רש״ר הירש].
Another perspective suggests a functional division. The earlier vessels represent the furnishings of a divine dwelling, whereas the incense altar is a tool of human worship, making its natural place alongside the laws of the priestly service [קאסוטו]. Additionally, there is a fundamental legal distinction. Unlike the outer altar, the physical presence of the incense altar is not an absolute requirement for the service; if it were removed, incense could still be burned in its designated spot. Its separate placement in the text hints that it is an independent Commandment and does not prevent the Divine presence from resting among the people [הכתב והקבלה, מלבי״ם, נחל קדומים, ברכת אשר, פרדס יוסף].
Beyond its function, the inner golden altar holds deep symbolic meaning. While the outer copper altar uses animal sacrifices to atone for the physical body and the animalistic soul of a person, the inner altar atones for the pure, spiritual soul. The rising smoke of the incense mirrors the nature of the soul itself, constantly yearning to return to its heavenly source [כלי יקר, מלבי״ם]. The service performed here is characterized by complete intimacy. When the incense is burned, no one else is present in the sanctuary except the priest and God. This absolute privacy represents the highest level of serving God and performing acts of kindness. These are pure, internal actions done far from the public eye, without any desire for recognition [חומש קה״ת]. Furthermore, the incense reflects the boundless power of such acts of kindness, which provide support and strength to the Torah itself [העמק דבר].
Finally, this altar and its incense possess a unique, miraculous quality. The fire burning upon it consumed very little and never damaged the gold plating or the acacia wood beneath it, as it was sustained by a heavenly fire [ספורנו, תורה תמימה]. Hidden within the secret of the incense is the power to stop plagues, soften strict divine judgment, and bring atonement to the Israelites through joy and mercy [רמב״ן, רבינו בחיי, רא״ש].