4:1 What causes fights [refers to a continual state of war; chronic hostilities as in a war] and quarrels [refers to individual conflicts or single encounters as in a battle] among you [the believers to whom he was writing]? Don’t they come from your desires [denotes sinful, sensual pleasures; implies physical cravings associated with bodily appetites; our Eng. word “hedonism” derived from Gr. word] that battle within you?
4:2 You want [to yearn for or crave; to lust or covet; anxious seeking] something but don’t get it. You kill [murder] and covet [to burn with envy; to be filled with jealousy; to grasp at what is not ours], but you cannot have what you want. You quarrel and fight [cf. Jas. 4:1]. You do not have, because you do not ask [in prayer; with an attitude of humility] God [only God can satisfy all our needs].
4:3 When you ask [on those occasions when they actually prayed], you do not receive, because you ask with wrong motives [literally means “with evil intent”], that you may spend [squander or waste] what you get on your pleasures [cf. “desires” in 4:1].
Note: How would you evaluate your prayers? What percentage of your requests could be classified as selfish?
4:4 You adulterous people [spiritual unfaithfulness], don’t you know that friendship [such friendship is evidence of spiritual unfaithfulness] with the world [the system of evil controlled by Satan; cf. 1 Jn. 5:19] is hatred toward God? Anyone who chooses to be a friend of the world becomes [is rendered or considered] an enemy of God.
4:5 Or do you think Scripture [use here inclusive of OT and Paul’s writings] says without reason [emptily or vainly] that the spirit [the inner part of our being] he caused to live in us envies intensely?
4:6 But he gives us more [greater] grace [God’s undeserved love and acceptance]. That is why Scripture says [cf. Prov. 3:34]: “God opposes [or resists: a military term meaning “to battle against”] the proud [those who attach undue importance to themselves] but gives grace [God shows His favor] to the humble [those who willingly submit to God and His ways].”
4:7 [note ten imperatives…]  Submit [to render obedience; to place oneself under God and His authority] yourselves, then, to God.  Resist [to take a stand against] the devil [literally “slanderer”], and he will flee from you.
Note: Why is it necessary to submit to God before resisting the devil?
4:8  Come near [an invitation to those who had drifted away from God because of their evil practices (cf. Jas. 4:1-4)] to God [the place of safety] and he will come near to you [like father of prodigal son (Lk. 15:11-32)].  Wash [because sin makes us unclean] your hands [represent our lifestyles and behaviors], you sinners, and  purify your hearts, you double-minded [those who tried to be friends with world and God; cf. Jas. 1:8].
4:9  Grieve [means “to be sorrowful” because of awareness of sin],  mourn [passionate grief or sorrow] and  wail [outward display of grief].  Change [means “to turn about”] your laughter to mourning and your joy to gloom [a downcast look or a feeling of heaviness].
4:10  Humble [means to recognize who we are and who God is] yourselves before the Lord, and he will lift [exalt] you up.
4:11 Brothers, do not [quit the habit of] slander [to speak against other person] one another. Anyone who speaks against his brother or judges him speaks against the law and judges it [probably refers to the royal law (cf. Jas. 2:8)]. When you judge the law, you are not keeping it, but sitting in judgment on it.
4:12 There is only one Lawgiver and Judge, the one who is able to save and destroy. But you—who are you to judge your neighbor?
4:13 Now listen, you who say, “[travel schedule…] Today or tomorrow we will go to this or that city, [time schedule…] spend a year there, [business schedule…] carry on business and make money.”
4:14 Why, you do not even know what will happen tomorrow. What is your life? You are a mist that appears for a little while and then vanishes [cf. Ps. 39:4-6; 103:14-16].
Note: What is the difference between boastful presumption and wise planning?
4:15 Instead, you ought to say, “If it is the Lord’s will, we will live and do this or that.”
4:16 As it is, you boast and brag. All such boasting [presumptuous and arrogant boasting] is evil.
4:17 Anyone, then, who knows the good he ought to do and doesn’t do it [sins of omission], sins.