Job's response to his friends has a sharp edge, but also includes some remarkable expressions of faith.
Chapter 12 Job's friends overestimate their own knowledge and underestimate Job's (v.1-3). This pitfall must be considered when one presumes to gives advice. Job's own case disproves their point that the blameless are never ridiculed (v.4-5), and his friends have brushed aside other evidence (v.6). If even the animals know that God is sovereign (v.7-10), how can Job's friends proclaim that point with such a sense of discovery? Job can confess God's sovereignty with conviction and with much more balance. The reversals of life, as well as its opposing forces and unexpected developments, are all within the power and wisdom of God (v.13-25).
Chapter 13 Job proclaims his own knowledge only because his friends have underestimated it (v.1-2). Having said too much already, it would be their wisdom to say no more (v.5). God does not need men to justify His works or distort the evidence in His favor (v.7-12). Job knows the hazards of claiming his own innocence (v.13-15), but his conscience remains clear and he will still make his case (v.15-19). No matter the outcome, he is resolved to trust God unto death (cf. Phil 2:8). Job 13:15 is a very high expression of selfless faith submitted to God's wise providence. Though his conscience is clear, Job is ready to know the worst about himself in humility and own the consequences of old sins. James 5:11 commends these graces.