Psalm 51:7

Thou cleansest me with hyssop and I am clean, Washest me, and than snow I am whiter.

Isaiah 1:18

Come, I pray you, and we reason, saith Jehovah, If your sins are as scarlet, as snow they shall be white, If they are red as crimson, as wool they shall be!

Hebrews 9:19

for every command having been spoken, according to law, by Moses, to all the people, having taken the blood of the calves and goats, with water, and scarlet wool, and hyssop, he both the book itself and all the people did sprinkle,

1 John 1:7

and if in the light we may walk, as He is in the light -- we have fellowship one with another, and the blood of Jesus Christ His Son doth cleanse us from every sin;

Exodus 12:22

and ye have taken a bunch of hyssop, and have dipped it in the blood which is in the basin, and have struck it on the lintel, and on the two side-posts, from the blood which is in the basin, and ye, ye go not out each from the opening of his house till morning.

Leviticus 14:4-7

and the priest hath commanded, and he hath taken for him who is to be cleansed, two clean living birds, and cedar wood, and scarlet, and hyssop.

Leviticus 14:49-52

'And he hath taken for the cleansing of the house two birds, and cedar wood, and scarlet, and hyssop;

Numbers 19:18-20

and a clean person hath taken hyssop, and hath dipped it in water, and hath sprinkled on the tent, and on all the vessels, and on the persons who have been there, and on him who is coming against a bone, or against one pierced, or against the dead, or against a grave.

Ephesians 5:26-27

that he might sanctify it, having cleansed it with the bathing of the water in the saying,

Hebrews 9:13-14

for if the blood of bulls, and goats, and ashes of an heifer, sprinkling those defiled, doth sanctify to the purifying of the flesh,

Revelation 1:5

and from Jesus Christ, the faithful witness, the first-born out of the dead, and the ruler of the kings of the earth; to him who did love us, and did bathe us from our sins in his blood,

Revelation 7:13-14

And answer did one of the elders, saying to me, 'These, who have been arrayed with the white robes -- who are they, and whence came they?'

Treasury of Scripture Knowledge

Summary

Purge me with hyssop, and I shall be clean: wash me, and I shall be whiter than snow.

Bible References

Purge

Leviticus 14:4
and the priest hath commanded, and he hath taken for him who is to be cleansed, two clean living birds, and cedar wood, and scarlet, and hyssop.
Numbers 19:18
and a clean person hath taken hyssop, and hath dipped it in water, and hath sprinkled on the tent, and on all the vessels, and on the persons who have been there, and on him who is coming against a bone, or against one pierced, or against the dead, or against a grave.
Hebrews 9:19
for every command having been spoken, according to law, by Moses, to all the people, having taken the blood of the calves and goats, with water, and scarlet wool, and hyssop, he both the book itself and all the people did sprinkle,

And

Hebrews 9:13
for if the blood of bulls, and goats, and ashes of an heifer, sprinkling those defiled, doth sanctify to the purifying of the flesh,
1 John 1:7
and if in the light we may walk, as He is in the light -- we have fellowship one with another, and the blood of Jesus Christ His Son doth cleanse us from every sin;
Revelation 1:5
and from Jesus Christ, the faithful witness, the first-born out of the dead, and the ruler of the kings of the earth; to him who did love us, and did bathe us from our sins in his blood,

Whiter

Isaiah 1:18
Come, I pray you, and we reason, saith Jehovah, If your sins are as scarlet, as snow they shall be white, If they are red as crimson, as wool they shall be!
Ephesians 5:26
that he might sanctify it, having cleansed it with the bathing of the water in the saying,
Revelation 7:13
And answer did one of the elders, saying to me, 'These, who have been arrayed with the white robes -- who are they, and whence came they?'

General references

Leviticus 15:5
and any one who cometh against his bed doth wash his garments, and hath bathed with water, and been unclean till the evening.
Leviticus 16:30
for on this day he maketh atonement for you, to cleanse you; from all your sins before Jehovah ye are clean;
Numbers 19:6
and the priest hath taken cedar wood, and hyssop, and scarlet, and hath cast unto the midst of the burning of the cow;