And Moses said to Aaron, “Take your censer, and put fire on it from off the altar and lay incense on it and carry it quickly to the congregation and make atonement for them, for wrath has gone out from the Lord; the plague has begun.” So Aaron took it as Moses said and ran into the midst of the assembly. And behold, the plague had already begun among the people. And he put on the incense and made atonement for the people. And he stood between the dead and the living, and the plague was stopped.
NUMBERS 16:48 ESV

There is a picture of Jesus here in these words. Is this not Him, what He does? Sometimes even without saying, the work of the cross is foreshadowed undeniably. The people were wrong, rightfully deserving of punishment. It’s not that God didn’t love them, but because of His holiness he could not allow their sins & ours to go unpunished. Because He is holy and also & at the same time just, sin has to be paid for. Even His judgement is out of love. Why, because our sin is wrong & corrupts us, corrupts His desire for His world that He created & spoke of calling it good, it infects the camp. And because of this love He provided means of payment, substitution through sacrifices in our place. In those days, only temporary solutions could be offered. So even though rightly deserving punishment, the children of Israel are atoned for, they are covered, spared. And more revealing of Jesus, the ones who covered them and interceded had NOTHING to do with their wrong.
He is the propitiation for our sins, and not for ours only but also for the sins of the whole world.
1 JOHN 2:2 ESV
God could have spared Moses and Aaron and wiped everyone else out. He’d even told them to step aside so He could. “The LORD said to Moses and Aaron, separate yourselves from this assembly so I can put an end to them at once (Numbers 16:20-21 NIV). Like the legions of angels Jesus had at His command, “Do you think I cannot call on my Father, and He will at once put at my disposal more than twelve legions of angels (Matthew 26:53 NIV)?” there could have been a wipeout. But they pleaded constantly on behalf of the people. Sound familiar, “Father, forgive them for they know not what they do. (Luke 23:34 NIV)

Sin is an urgent issue. “HURRY to the assembly to make atonement for them.” The plague of sin had already started corrupting our world from the time of the fall & the only suitable response to that plague was wrath from God. “For the wages of sin is death…” Had Jesus not taken our place this would have been our fate. “…but the gift of God is eternal life through Jesus Christ our Lord (Romans 6:23).” It brings to mind the writer of Hebrews speaking of Jesus during His life on earth with fervent cries and tears, offering prayers and petitions (Hebrews 5:7). How precious is the gift of atonement! That someone stood between the dead and the living and the plague stopped. That Aaron ran to do it, he didn’t walk because the plague was already ravaging the camp. 14,700 people would die here. Death was moving, but the offering he made as High Priest, the only one worthy in their midst to offer this incense before God covered them. It covered those rightfully deserving death. Think of the 250 men who had just died for trying to do the same in their own power because they felt like they were deserving of the priesthood. Something they didn’t even near understand the significance of. We could never and can never save ourselves.
Every high priest is selected from among the people and is appointed to represent the people in matters related to God, to offer gifts and sacrifices for sins. He is able to deal gently with those who are ignorant and going astray, since he himself is subject to weakness. This is why he has to offer sacrifices for his own sins, as well as for the sins of the people. And no one takes this honor on himself, but he receives it when called by God, just as Aaron was.
HEBREWS 5:2-4
God shows how much we couldn’t through the law and sacrificial system and then perfected and completed the only lasting way through Jesus. Making Him our way where there wasn’t one. The priest with intercession in his hand, running to cover guilty people. But even greater than Aaron and stopping an even greater plague than here in these verses in Jesus.
Son though He was, He learned obedience from what He suffered and once made perfect, He became the source of eternal salvation for all who obey Him and was designated by God to be high priest in the order of Melchizedek.
HEBREWS 5:8-10

He stood between the dead and the living. I can’t help but see the cross. I can’t help but see the hope of a far greater glory to come. An anchoring hope they anticipated but one we can experience the fulfilment of. Thankful for the one who tore the veil in His death and defeated that same death in His resurrection.
We have this hope as an anchor for the soul, firm and secure. It enters the inner sanctuary behind the curtain, where our forerunner, Jesus, has entered on our behalf. He has become a high priest forever, in the order of Melchizedek. HEBREWS 6:19-20