There are a multiplicity of things for which we as frail human beings need grace, but I think it better to acknowledge our need of grace not for many things, but for all things.
When I think of Paul and his struggle with "a thorn in the flesh" I acknowledge that it must have been a troubling thorn indeed. It was, after all, given to him as a means of keeping him humble in the face of his extraordinary privileges in Christ, even that of being caught up into Paradise and receiving inexpressible revelation from God. Off the top I can only think of three other men who encountered visions of heaven (Isaiah, Ezekiel and John), limiting this privilege to a select few to be sure, however Paul was even more unique in that he received his training through one-on-one encounters with the risen Lord over a period of several years. I think he may be the only one ever to live to have had such a rich measure of discipleship; such a deep and thorough acquaintance with Christ Himself. You would think such a man could encounter anything and remain unphased, and yet, that "thorn."
I do not count myself too ashamed to acknowledge that I too experience weakness and need; I too suffer with pains I would rather have removed. It matters not that my struggles can not compare with those of Paul (for Christians are not called to compare themselves by themselves) rather, our struggles whatever they be cause us to see our need of grace.
The lesson of the "thorn" is not that we ought to carry on in pride when it comes to matters that we are capable of handling, and then cling to grace in those few matters of difficulty. No! Rather, the lesson is that each of us live at all times in a state of weakness and dependence upon the Lord, and it is in that state that we ought to rejoice, for as Paul says, "When I am weak, then I am strong." Paul's struggles never eased up and his "thorn" never went away, serving constantly to remind him of his need of Christ. How simple it is to see why he took pleasure in his infirmities...for one who lives in an infirmed state knows by experience that those things which hamper us can do nothing to hamper Christ; those things we regard as useless are held subject to One who would make them useful.
"My grace is sufficient for you, for My strength is made perfect in weakness."
