Let me start by saying that I hold no negative thoughts toward anyone who signed the recent Statement on Social Justice & the Gospel. I may even do so myself, once I’ve given it more thought.
My leading reservation isn't spelled out in The Xian AnCap’s most recent article; not in quite the depth necessary to explain it, anyway. However, The Xian AnCap and I are working together on a series of articles for greater elaboration. So, while I appreciate John MacArthur (and those who helped articulate the statement), I believe there are underlying presuppositions that diminish its intent — even though MacArthur’s most recent article may be a greater reflection of his own thoughts (I can’t say for certain).
I believe that the Gospel is paramount, and that earthly justice is imperfect (at least until the second coming), but none of this negates the Christian’s responsibility towards seeking justice and loving mercy. This is why I believe the part in the statement on justice is weak (see Affirmations & Denials, III).
As sojourners, we can't minimize the call to justice. In fact, we need to be louder than the “SJWs." In MacArthur’s aforementioned article, he makes up for the lacking substance in the Statement when he says,
Doing justice (i.e., biblical justice, not the secular substitute) together with loving mercy and walking humbly with God are all essential virtues. Those are the chief practical duties incumbent on every believer (Micah 6:8).
If this were included in the original statement, I wouldn’t be so hesitant to sign it.
Anyone who knows me knows my libertarian views weren't created in a vacuum, or by reading Murray Rothbard. I genuinely sought a political theory that was consistent with the above call to justice and mercy. Now I can say - with greater consistency than MacArthur - that God’s Law demands
a strong work ethic, enforced by the principle that able-bodied people who refuse to work shouldn’t benefit from public charity (1 Thessalonians 4:11; 2 Thessalonians 3:10).
It’s not simply because of a Biblicist exposition of isolated New Testament precepts, but because of a Biblical Theology that allows a consistent application of God’s eternal moral law in general equity — charity being a responsibility of volunteers and not of State officials who must then breech God’s Law to that end.
I know people won't be quickened to immediate and just recourse in things like abortion, protracted wars, Socialist policies, etc., if they are at all. Regardless, contrary to MacArthur's exposition of Colossians 3:2, as what I see as an overreaction to the mantra against being “so heavenly minded that we're of no earthly good," heavenly-mindedness entails absolute adherence to Scripture in all things, including “compassionate hearts” (cf. Col. 3:12ff). It doesn't mean "monastic flight," as Kuyper would call it — where we give mere lip service to justice and mercy.
It means having a worldview that’s informed by Scripture (ironically given by God’s divine mind), that addresses all facets of life, including, and especially, political and economic theory (i.e. justice and mercy). It means preaching outside of abortion mills, calling government officials to repent for the various crises they’ve created (civilly and economically), and never using initiatory violence to effect social morality. God is our only recourse; not man.
We can’t seek justice and love mercy without actually seeking justice and loving mercy. This in no way should distract from the Gospel, but it should be an indication of a living faith in the truth of the Gospel (cf. Jas. 2:14-16).