Numbers 19:9

And one that is clean, shall go and take up the ashes of the cow, and put them without the host in a clean place, where they shall be kept to make sprinkling water for the multitude of the children of Israel: for it is a sin offering.

Numbers 19:13

Whosoever toucheth any person that dieth and sprinkleth not himself, defileth the dwelling of the LORD: and therefore that soul shall be rooted out of Israel, because he hath not sprinkled the sprinkling water upon him, he shall be unclean, and his uncleanness shall remain upon him.

Hebrews 9:13

For if the blood of oxen, and of goats, and the ashes of a heifer, when it was sprinkled, purified the unclean, as touching the purifying of the flesh:

Numbers 19:20-21

"'If any be unclean and sprinkle not himself, the same soul shall be destroyed from among the congregation: for he hath defiled the holy place of the LORD. And he that sprinkleth the sprinkling water, shall wash his clothes.

Leviticus 15:20

And all that she lieth or sitteth upon as long as she is put apart shall be unclean.

Numbers 6:12

and he shall abstain unto the LORD the time of his abstinency, and shall bring a lamb of an year old for a trespass offering: but the days that were before are lost, because his abstinence was defiled.

Numbers 8:7

And this do unto them when thou cleansest them: sprinkle water of purifying upon them and make a razor to run along upon all the flesh of them, and let them wash their clothes, and then they shall be clean.

Numbers 9:13

But if a man be clean and not let in a journey, and yet was negligent to offer Passover, the same soul shall perish from his people, because he brought not an offering unto the LORD in his due season: and he shall bear his sin.

Numbers 19:18

And a clean person shall take Hyssop and dip it in the water, and sprinkle it upon the tent and upon all the vessels and on the souls that were there, and upon him that touched a bone or a slain person or a dead body or a grave.

Numbers 31:23-24

and all that may abide the fire, ye shall make it go through the fire, and then it is clean. Neverthelater, it shall be sprinkled with sprinkling water. And all that suffereth not the fire, ye shall make go through the water.

Zechariah 13:1

In that time shall the house of David and the citizens of Jerusalem have an open well, to wash of sin and uncleanness.

2 Corinthians 5:21

for he hath made him to be sin for us, which knew no sin, that we by his means should be that righteousness which before God is allowed.

2 Corinthians 7:1

Seeing that we have such promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, and grow up to full holiness in the fear of God.

Hebrews 7:26

Such a high priest it becometh us to have, which is holy, harmless, undefiled, separate from sinners, and made higher than heaven.

Treasury of Scripture Knowledge

Summary

And a man that is clean shall gather up the ashes of the heifer, and lay them up without the camp in a clean place, and it shall be kept for the congregation of the children of Israel for a water of separation: it is a purification for sin.

Lay them up

General references

Bible References

Clean

Numbers 19:18
And a clean person shall take Hyssop and dip it in the water, and sprinkle it upon the tent and upon all the vessels and on the souls that were there, and upon him that touched a bone or a slain person or a dead body or a grave.
Numbers 9:13
But if a man be clean and not let in a journey, and yet was negligent to offer Passover, the same soul shall perish from his people, because he brought not an offering unto the LORD in his due season: and he shall bear his sin.
2 Corinthians 5:21
for he hath made him to be sin for us, which knew no sin, that we by his means should be that righteousness which before God is allowed.
Hebrews 7:26
Such a high priest it becometh us to have, which is holy, harmless, undefiled, separate from sinners, and made higher than heaven.
Hebrews 9:13
For if the blood of oxen, and of goats, and the ashes of a heifer, when it was sprinkled, purified the unclean, as touching the purifying of the flesh:

Lay them up

Numbers 19:17
And they shall take for an unclean person, of the burnt ashes of the sin offering, and put running water thereto into a vessel.

A water of separation

Leviticus 15:20
And all that she lieth or sitteth upon as long as she is put apart shall be unclean.
Zechariah 13:1
In that time shall the house of David and the citizens of Jerusalem have an open well, to wash of sin and uncleanness.
2 Corinthians 7:1
Seeing that we have such promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, and grow up to full holiness in the fear of God.

General references

Leviticus 22:6
the same soul that hath touched any such thing, shall be unclean until even, and shall not eat of the hallowed things until he have washed his flesh with water.
Numbers 19:18
And a clean person shall take Hyssop and dip it in the water, and sprinkle it upon the tent and upon all the vessels and on the souls that were there, and upon him that touched a bone or a slain person or a dead body or a grave.