The distinction between things which were ritually acceptable and unacceptable to God. Animals were classified as either clean or unclean, denoting their suitability or unsuitability for sacrifice and food. The motives and intentions of the heart were also sometimes judged to be clean or unclean, as uncleanness was often linked with sin.
The OT distinction between clean and unclean
The command to distinguish between clean and unclean
Leviticus 15:31 See also Leviticus 10:8–11, Leviticus 20:22–26; Ezekiel 22:26, Ezekiel 44:23
You must keep the children of Israel separate from their uncleanness, so that they do not die by defiling My tabernacle, which is among them.
The distinction between clean and unclean animals
Genesis 7:2 See also Genesis 7:8–9, Genesis 8:20; Leviticus 11:1–47 parallel Deuteronomy 14:3–20; Leviticus 27:11–13
You are to take with you seven pairs of every kind of clean animal, a male and its mate; a pair of every kind of unclean animal, a male and its mate;
The NT attitude to clean and unclean animals
Mark 7:14–23 parallel Matthew 15:10–20; Acts 10:11–15, Acts 11:5–9
Places and inanimate objects could be clean or unclean
Leviticus 10:14 See also Leviticus 4:12, Leviticus 6:11, Leviticus 11:32–38, Leviticus 14:33–57; 2 Chronicles 13:11
And you and your sons and daughters may eat the breast of the wave offering and the thigh of the contribution in a ceremonially clean place, because these portions have been assigned to you and your children from the peace offerings of the sons of Israel.
Causes of uncleanness
Physical contact with anything unclean
Leviticus 5:2–3 See also Leviticus 7:19; Hosea 9:3–4; Haggai 2:10–14
Or if a person touches anything unclean— whether the carcass of any unclean wild animal or livestock or crawling creature— even if he is unaware of it, he is unclean and guilty. Or if he touches human uncleanness— anything by which one becomes unclean— even if he is unaware of it, when he realizes it, he is guilty.
Contact with corpses
Numbers 19:11 See also Leviticus 21:1–4, Leviticus 21:10–12; Numbers 6:5–8
Whoever touches any dead body will be unclean for seven days.
Infectious skin diseases
Leviticus 13:1–46 See also Leviticus 14:1–32; Matthew 8:2–4 parallels Mark 1:40–44, Luke 5:12–14
Certain bodily functions
Leviticus 12:2 See also Leviticus 12:5, Leviticus 15:1–33
“Say to the Israelites, ‘A woman who becomes pregnant and gives birth to a son will be unclean for seven days, as she is during the days of her menstruation.
Consequences of uncleanness
Exclusion from worship
Leviticus 22:3–5 See also Leviticus 12:4; Numbers 9:6–12; 1 Samuel 20:24–26; 2 Chronicles 23:19, 2 Chronicles 30:17
Tell them that for the generations to come, if any of their descendants in a state of uncleanness approaches the sacred offerings that the Israelites consecrate to the LORD, that person must be cut off from My presence. I am the LORD. If a descendant of Aaron has a skin disease or a discharge, he may not eat the sacred offerings until he is clean. Whoever touches anything defiled by a corpse or by a man who has an emission of semen, or whoever touches a crawling creature or a person that makes him unclean, whatever the uncleanness may be —
Isolation from God's people
Numbers 5:2 See also Leviticus 7:20–21; Deuteronomy 23:10–11
“Command the Israelites to send away from the camp anyone with a skin disease, anyone who has a bodily discharge, and anyone who is defiled by a dead body.
Cleansing from uncleanness
Leviticus 16:29–30 See also Leviticus 12:6–8, Leviticus 16:15–16, Leviticus 22:4–7; Numbers 6:9–12, Numbers 19:1–22, Numbers 31:21–24; Hebrews 9:13
This is to be a permanent statute for you: On the tenth day of the seventh month, you shall humble yourselves and not do any work — whether the native or the foreigner who resides among you — because on this day atonement will be made for you to cleanse you, and you will be clean from all your sins before the LORD.
Inner, spiritual cleanness and uncleanness
Job 33:9; Psalm 51:7 See also Genesis 20:5; Psalm 24:3–4; Proverbs 20:9; Isaiah 1:15–16, Isaiah 64:6; Lamentations 1:8; Ezekiel 36:25; Matthew 15:10–20 parallel Mark 7:14–23; Matthew 23:25–28; Acts 10:28
‘I am pure, without transgression; I am clean, with no iniquity in me.
Purify me with hyssop, and I will be clean; wash me, and I will be whiter than snow.
Related themes
Dictionary of Bible Themes © 1999 Martin Manser, licensed CC BY-SA 4.0, via Bible Aquifer. Formatted for this site, with Scripture from the Berean Standard Bible.