From a profound little book called The Christian and Anxiety, on weakness, defenselessness, and the paradoxical, left-handed strength that may spring from them:

Of all things, defenselessness and, from the natural human perspective, weakness (and, last but not least, anxiety) now become the essential prerequisites for Christian fortitude. Right where I become serious about baring my heart and my life, the real power (which is not mine but God’s) radiates most purely. ‘But we have this treasure in earthen vessels, to show us that the transcendent power belongs to God and not to us.’ We are oppressed on every side but are not made anxious; ‘perplexed, but not driven to despair; persecuted, but not forsaken; struck down, but not destroyed.’ (2 Cor 4:7-9), ‘but he said to me, ‘My grace is sufficient for you, for my power is made perfect in weakness.’ I will all the more gladly boast of my weakness… for when I am weak, then I am strong’ (2 Cor 12:9-10). Ever-increasing defenselessness is an ever-increasingly open stance toward God and for God, and hence an ever-increasing influx and indwelling of God’s power in man. No one is as unarmed and exposed as the saint is before God, and therefore no one is as ready to be deluged by every anxiety; yet this is the quintessence of courage and armament – by God.