Today's first reading from Jeremiah describes the Israelites' response to God's commands: "They obeyed not, nor did they pay heed. They walked in the hardness of their evil hearts and turned their backs, not their faces, to me. From the day that your fathers left the land of Egypt even to this day, I have sent you untiringly all my servants the prophets. Yet they have not obeyed me nor paid heed; they have stiffened their necks and done worse than their fathers" (Jer. 7: 25-26). Over and over in the Pentateuch, the Lord uses this peculiar epithet, stiff-necked, for the children of Israel. It means something along the lines of stubborn or obstinate.
Today this passage struck me because I have a very stiff neck right now. (I'm not really sure why, but think it has something to do with jumping on a trampoline.) Anyway, it just occurred to me to ask: what is so bad about having a stiff neck? After all, we're also called to walk the straight and narrow, and to look neither to the left nor to the right.
Perhaps this psalm provides an answer: "To thee I lift up my eyes, O thou who art enthroned in the heavens! Behold, as the eyes of servants look to the hand of their master, as the eyes of a maid to the hand of her mistress, so our eyes look to the Lord our God, till he have mercy upon us" (Ps. 123:1-2). With a neck which is spiritually stiff, we're unable to raise our eyes to heaven and keep them fixed faithfully on the Lord.
Conversely, we're also called to bear the yoke of the Lord and to bend ourselves to his will. Perhaps this sounds like it would result in a stiff neck rather than being the cure for a stiff neck, but I think not. After all, the Lord is the one who fashioned our necks, and indeed our whole body and soul. Surely then He knows best how to keep our necks in good working order. They need to be pliable and supple enough to do His will as it is revealed to us in every moment, rather than stubbornly insisting on our own will.
And if I do my spiritual exercises every day and alternate raising my eyes to the Lord and bowing submissively before him, perhaps I won't be able to complain about my stiff neck anymore.