I liked this section from Tom Wright's latest book 'Justification'. Taking John Piper to task for his rather idiosyncratic understanding of the 'righteousness of God' as 'God's concern for God's own glory' he says
'...the great story of scripture, from creation and covenant right on through to the New Jerusalem, is constantly about God's overflowing, generous, creative love - God's concern, if you like, for the flourishing and well-being of everything else. Of course, this too will redound to God's glory because God, as the creator, is glorified when creation is flourishing and able to praise him gladly and freely. And of course there are plenty of passages where God does what he does precisely not because anybody deserves it but simply 'for the sake of his own name'. But 'God's righteousness' is regularly invoked in scripture, not when God is acting thus, but when his concern is going out to those in need, particularly to his covenant people.
The 'righteousness of God' is an outward-looking characteristic of God, linked of course to the concern for God's own glory but essentially going, as it were, in the opposite direction, that of God's creative, healing, restorative love. God's concern for God's own glory is precisely rescued from the appearance of divine narcissism because God, not least God as Trinity, is always giving out, pouring out, lavishing generous love on undeserving people, undeserving Israel, and an undeserving world. That is the sort of God he is, and 'God's righteousness' is a way of saying, Yes, and God will be true to that character...' p51-52