The subject of Proverbs 30:33 is the inevitability of strife and contention when a sinner gives rein to anger. Two common illustrations serve as physical models to express the truth.
Proverbs 30:33 – “Surely the churning [pressure; forcing; wringing] of milk bringeth forth [proceed; bring out; i.e. produces] butter, and the wringing [pressure; forcing; wringing] of the nose [nostril; i.e. anger, wrath] bringeth forth [proceed; bring out; i.e. produces] blood [of which the shedding of blood causes death]: so the forcing [pressure; wringing] of wrath [same as “nose” indicating anger; quick-tempererd] bringeth forth [proceed; bring out; i.e. produces] strife [contention; controversy; adversary; dispute].”
The ancient work of churning fresh milk to make butter is an unfamiliar activity in our day of big-box grocery stores with refrigerator shelves lined with a variety of commercially produced butters and margarines. I cherish a faint memory of my fraternal grandmother churning butter in her kitchen, sitting on a slat kitchen chair and aggressively working a wood paddle up and down in a clay fired jar. Her churning slowly brought forth butter.
The second picture is the physical reality that excessive blowing of the nose or a blow to the nose in a fistfight will produce the inevitable–a stream of blood and a bloody nose.
Understanding attitudes and actions have consequences (churning fresh milk produces butter and a blow to the nose brings forth blood), a third inevitability is stated: A sinner harboring an angry, bitter spirit will provoke strife and fighting.
Anger and bitterness are emotions that rage in the bosom of foolish sinners, too proud to see their pride and self-centeredness is at the root of a majority of the conflicts in their lives. 
Unresolved disagreements and a vengeful, self-centered spirit will destroy friendships, marriages, and families. Threats, fighting and lawsuits are symptomatic of a people who churn within and are unwilling to take responsibility for their sinful attitudes and actions.
We would all do well to heed Paul’s exhortations to the church in Ephesus:
Ephesians 4:26-27, 31-32 – “Be ye angry, and sin not: let not the sun go down upon your wrath: 27 Neither give place to the devil….31 Let all bitterness, and wrath, and anger, and clamour, and evil speaking, be put away from you, with all malice: 32 And be ye kind one to another, tenderhearted, forgiving one another, even as God for Christ’s sake hath forgiven you.”
Copyright 2015 – Travis D. Smith