“While the Lord took knowledge of the enfeebled frame of His servant, yet He did not for that reason encourage him to be slack. On the contrary, He assigned him a new, though much lighter task. It is not the revealed will of God that His people should spend their old age in idleness. He does not preserve them through all the dangers of youth and the trials of maturity that they should be mere cumberers of the ground. He may well suffer them to become exceedingly tottery and perhaps bedridden and entirely dependent upon others, yet even so, it is their privilege and duty to beg Him to make good in them that precious word, “They shall still bring forth fruit in old age: they shall be fat and flourishing” (Psalm 92:14).
They may still commune with the Lord, and manifest the effects thereof. The decay of nature is no reason why grace should languish. Even when thoroughly helpless, the fruits of patience, meekness and gratitude may be borne, and they may carry themselves as the monuments of God’s goodness and the memorials of His faithfulness, and thereby “show forth his praises.” Though the strenuous efforts of earlier years be no longer possible, the ministry of prayer is available unto the very end, and who can say that more will not be accomplished therein for eternity than by any other spiritual activity?

~ Arthur Pink, “The Life and Times of Joshua”