Daily discipleship is a daily call to die (Luke 9:23, par.). Each believer resonates with this, and although it cuts against the grain of his heart, he nonetheless longs to be an even more faithful and committed disciple.
But it is also true that on many occasions we find ourselves utterly weak: we have little desire to be in the word or in prayer, or creeping doubts about God’s character and love, or a frustrating inability to overcome certain besetting sins. The list, you know, could go on. Such is the life of the disciple in the “already-not yet” pilgrim path.
The comforting reality is that God uses these moments of weakness—whether a physical infirmity or inward frustration or any other affliction or trial in life—to teach us dependence upon him and him alone. When emptied of ourselves we are then able to be filled with God. “Therefore I will boast all the more gladly of my weaknesses, so that the power of Christ may rest upon me” (2 Cor. 12:9).
Charles Hodge drives this truth home:
When really weak in ourselves, and conscious of that weakness, we are in the state suited to the manifestation of the power of God. When emptied of ourselves, we are filled with God. Those who think they can change their own hearts, atone for their own sins, subdue the power of evil in their own souls or in the souls of others, who feel able to sustain themselves under affliction, God leaves to their own resources. But when they feel and acknowledge their weakness, he communicates to them divine strength.
God, who knows our frame and our pride, rather than leaving us to our own devices, lovingly rids us of ourselves to showcase his own sufficiency. God gets the glory, we get the grace. What comfort that is to weary and weak souls!
 Charles Hodge, An Exposition of the Second Epistle to the Corinthians [Grand Rapids, 1973 reprint], 289.