I thought I would get to writing on this a week or so ago, but better late than never. If you want to read through the question posed by Dr. Moore go here. The question reminded me how fallen our world is and how complicated situations are. It's easy to sloganeer our way through issues like immigration and undocumented workers, but when you really enter the situation you see how convoluted and confusing it is.
In situations like Pablo's where he seems stuck between two conflicting norms - obey the law and provide for your family, there exists three main positions. First, some hold what is termed a "conflicting absolutes" or "lesser of two evils" position. Basically, Christians holding this position argue that in our fallen world, sometimes two or more principles of moral behavior will conflict absolutely and there is no option in such situations but to sin. If that is the case, the Christian should weigh in the balance the two options, choose the lesser of the two evils, and then 'sin boldly', but repent later. So, Pablo should continue to live and work in the States, providing for his family, he should confess it as sin (this assumes, of course, that the value of Pablo's family is deemed to be greater than the value of obeying a arguably unjust law that would make their survival impossible).
The second position is sometimes labeled "hierarchical-ism". Those in this camp hold that there is an ordered hierarchy of absolutes, "such that some values have priority over others." When these values conflict and it's impossible to follow both absolutes, one should act according to the higher norm. Sounds a lot like the first, except that those who hold to a hierarchical view don't see the violation of the lesser norm as sin, not when it is in conflict with a greater norm. So, Pablo should continue to live and work in the States and feel no guilt, nor feel the need to confess it as sin (again, assuming that we put a higher premium on Pablo's family than national borders).
The third position is one of "non-conflicting absolutes". Proponents of this view argue that even when absolutes seem to conflict, in reality there is always a 'third way' out of the situation that avoids sin. Not to opt for the third way is sin. Pablo, on this view, should look for a third alternative which most certainly exists. Maybe he can get a better job than he thinks in his country of origin and continue to provide for his family. Maybe he could hire a lawyer and fight for legal status, etc.
Each position has it's strengths and weaknesses. The first is certainly counter intuitive - that God would hold someone as guilty of sin when they were constrained by the situation to commit a sinful act. The second position runs into the problem of a lack of biblical support. Nowhere do we encounter a hierarchy of sins or of norms, or any clear teaching that God will exempt us from the guilt of sinning if a higher good was in view (Rom. 3:7-8). Furthermore, that is certainly a slippery slope to Machiavellianism. The third position seems naive, but seems to line up with the biblical data best. Some have argued that to deny this third position, the "non-conflicting absolute" position, raises questions about God's ability to provide and about our faith in God's provision. Additionally, there is the biblical witness that God will provide a way of escape from sin/temptation (1 Cor. 10:13). Most importantly regarding the third position is the WWJD question. Yes, I'm being serious. The first position ("conflicting absolutes) raises questions about Jesus' sinlessness. If Jesus was tempted like we are, and if some of our temptations put us in situations where sin is inevitable, how can we maintain Jesus was sinless. The second position avoid this by saying that even in situations like Pablo's, had Jesus chosen as Pablo did, he wouldn't have been sinning.But, as seen above, this seems to rest on dubious groups Biblically.
My position is a combination of position one and three. I believe God does provide a way of escape from sin/temptation. I believe there is a 'third way' and Jesus is pretty good proof of it. So I agree with those who hold to position three - the 'non-conflicting norms' view. However, in this fallen world, our intellects aren't as sharp as they should be. We aren't as wise as God would have us be. We don't stay in step with the Spirit as Jesus did. So, we are sometimes faced with decisions where there doesn't seem to be a 'sinless' way out of it - where norms conflict. What should we do? Here I think position one is correct - we pick the lesser of the two evils. We violate a statute regarding citizenship to feed our families. In the case of Rahab, we lie to save lives. In the case of the Hebrew midwives, we again lie to save the lives of infant babies. We violate laws that prohibit the preaching of the gospel in closed countries. We smuggle Bibles into areas where it is forbidden. In those situations where we can't see a third way we act in a way that makes value judgements and choose honor those higher values. But ignorance isn't an excuse to sin. Trust me, I've tried it with police officers before - "sir I didn't know the speed limit was 35 here" or "sir, I didn't see the stop sign". So, in such situations where we've chose sin to avoid a greater sin, we should still confess it as such and trust in the free provision of God's grace for sinners. (My position is hard for many reasons, chief among them is that it cannot be absolutized. If the life of five more valuable than the life of one. Conjuring Spock: the needs of the many outweigh the needs of the few. Yes. Does that mean I should kill and rob one to feed five. No. Can we lie to save a life, like Rahab? Yes. Should we lie about our faith in Christ to keep from becoming a martyr? No.)
So, in Pablo's case, as his pastor, I would baptize him and admit him into full communion of the church. I would counsel him to confess his sin and pray earnestly that God would show him a way to support his family without violating the law.
Regarding the employer, I think much has to do with his motivations. Is he getting rich by exploiting his undocumented workers? Or, is he providing them with employment at a fair wage so that they can support their families? Again, if he's employing Pablo to prevent him and his family from starving, I would commend him for making a tough choice given bad options - a choice that is putting him and his business at risk.
Even here in Indiana, this issues isn't one that's far off or relegated to border states. Even if it were, there are other issues we face like it, though thankfully, not frequently. Usually, we can discern a third way (more so as we grow in wisdom and in reliance on the Spirit) - maybe not one that is comfortable or enjoyable, but I think it's rare that we face a situation in which there is no clear righteous solution.