Summary: The 1) Relational Struggle (Galatians 5:20b-21a) and 2) Personal Struggle (Galatians 5:21b) with sin.
If you are a fan of classic, dry humor, then you probably know Bob Newhart. There is a skit where he’s a Psychiatrist and a patient comes in. After he explains the billing process, she explains her problem. After listening, he replies that he wants to say just two words. I want you to take them out of the office and incorporate them into your life. Here they are: “STOP IT”. She responds: “But doctor, what do you mean?”. Two words: “S-T-O-P, new word, I-T”. “STOP IT”. “I don’t understand”, she said. He replied: “I can’t tell you the number of people who ask this, but it’s not Yiddish”. “STOP IT”. She objected” But my parents didn’t love me, my husband avoids me, my kids ridicule me and my boss, bullies me”. “We don’t go there”, he said. Just “STOP IT”. So I should just stop it then? There you go. You got it. You don’t want to go through life with your problem, so just “STOP IT”. If only dealing with our problems were that easy. (http://www.crosswaystolife.org/Dealing_with_Sin_and_Addiction.html)
When there are personal failings coupled with group conflict, the results are always disastrous. When the Apostle Paul wanted to contrast the life of a spirit filled Christian with someone dominated by the works of the flesh he commented on the nature of Sexual and religious defilement, impacting relational and personal struggles.
The struggle with sin marks one who is led by the Spirit. Someone who exists in the flesh does not struggle with what they are most comfortable with. In Galatians 5:20b-21, Paul now outlines several other pitfalls to watch out for in personal and group dynamics. Understanding the nature of these pitfalls helps us to avoid those things that will be destructive and provide personal directions for living a Spirit controlled life. It has a bearing on our personal, relational and divine relationship
When “Struggling with Sin” we must watch for the:
1) Relational Struggle (Galatians 5:20b-21a)
Galatians 5:20b-21a  (idolatry, sorcery), enmity, strife, jealousy, fits of anger, rivalries, dissensions, divisions,  envy, (drunkenness, orgies, and things like these. I warn you, as I warned you before, that those who do such things will not inherit the kingdom of God). (ESV)
Following a presentation of sins that defile sexually, and spiritually, the third group of sins relates to human relationships. It represents the breakdown of Christian community. These sins are against the neighbor, essentially a breaking of the Fifth Commandment. Here we see a degradation from feelings (e.g., hostilities) to actions (quarrels) to results (factions) Paul’s major emphasis in speaking of the Flesh lies on the ways in which that power destroys community life.( Martyn, J. L. (2008). Galatians: a new translation with introduction and commentary (Vol. 33A, p. 497). New Haven; London: Yale University Press.)
Quote: The Problem with sin is that it will TAKE YOU FARTHER THAN YOU PLANNED ON GOING, KEEP YOU LONGER THAN YOU PLANNED ON STAYING
and COST YOU MORE THAN YOU PLANNED ON PAYING. (Wade Martin Hughes, Sr. Kyfingers@aol.com)
The first on the list is one described as “Emnity/Hatred” (echthrai) which is in the plural form, denoting primarily a feeling of (hostility) between groups (Walvoord, John F. ; Zuck, Roy B. ; Dallas Theological Seminary: The Bible Knowledge Commentary : An Exposition of the Scriptures. Wheaton, IL : Victor Books, 1983-c1985, S. 2:607) It closely relates to the Greek work for enemy (echthros). This form of hatred includes any kind of political, racial, or religious hostility, whether public or private (Philip Graham Ryken. Galatians: Reformed Expository Commentary. P&R Publications 2005. p. 230). Racism, for example, is the spirit that looks with evil suspicion on anyone of a different race, tongue, nation, or creed (Boles, Kenneth L.: Galatians & Ephesians. Joplin, Mo. : College Press, 1993 (The College Press NIV Commentary), S. Ga 5:20)
This all reflects a way of life before becoming a Christian. As Paul described to Titus:
Titus 3:3  For we ourselves were once foolish, disobedient, led astray, slaves to various passions and pleasures, passing our days in malice and envy, hated by others and hating one another. (ESV)
A number of Greek manuscripts and some translations (KJV) include “murder” to this list. The New Testament Ethic explains what the intent of the law meant:
1 John 3:15  Everyone who hates his brother is a murderer, and you know that no murderer has eternal life abiding in him. (ESV)
• If the list of social sins here are meant to be seen as the mirror opposites of those qualities or actions listed as the fruit of the Spirit in vss. 22–23, then enmity/hatred is contrasted with love in this discussion (Witherington III, Ben: Grace in Galatia : A Commentary on St. Paul's Letter to the Galatians. Grand Rapids, MI : Wm. B. Eerdmans Publishing Co., 1998, S. 400)