If the problem in James 4:1-10 was the combination of a jealous God with an adulterous people, and the wonderful solution was God’s grace for those who humble themselves before him, then in 4:11-17 James fleshes this out with two examples – examples of what humility doesn’t look like.
Firstly (v11-12), humility doesn’t look like judging other people. God is judge, not us. So if we rightly recognise our place under God, we won’t judge others.
And secondly (v13-17), humility doesn’t look like making overly-confident claims about our future. No matter how much we want something or how hard we work for something – however certain it may seem – it will only happen “if the Lord wills”. So if we rightly recognise our place under God, we will recognise his sovereignty over all of our planning.
True humility is knowing our place under the Lord.