Arnold still continued his work at Rugby, remaining in part because two of his sons were being educated there. He was also making final arrangements for an edition of St. Paul's Epistles.
The last lecture of his first year at Oxford, June 2, 1842, was abandoned for the time, on account of a brief, but sudden illness. June 5 he preached his farewell sermon to the Rugby boys, before the vacation; and Friday, June 10, was the public-day for school speeches.
Saturday he was in high spirits, taking his usual walk and bath, and conversing with his guests on social and historical topics. In the evening he gave a supper to some of the higher classes of the school.
He wrote in his diary that evening, June 11, 1842: "The day after to-morrow is my birthday, if I am permitted to live to see it—my forty-seventh birthday since my birth. How large a portion of my life on earth is already passed.... But above all, let me mind my own personal work—to keep myself pure and zealous and believing—laboring to do God's will, yet not anxious that it should be done by me rather than by others, if God disapproves of my doing it."
Between five and six o'clock on Sunday morning he awoke with a sharp pain across his chest. He lay with his hands clasped and his eyes raised upwards, while he repeated, "And Jesus said unto him, Thomas, because thou hast seen me, thou hast believed: blessed are they that have not seen, and yet have believed."
Against Arnold's wish, his wife sent for a physician. Meantime she read to him in the Prayer Book, the fifty-first psalm. The twelfth verse, "O give me the comfort of thy help again, and establish me with thy free spirit," he repeated after her very earnestly.
The physician soon came, and Arnold, asking the cause of the pain, was told that it was spasm of the heart.
"Is it generally fatal?" asked Arnold. "Yes, I am afraid it is," was the reply.
Soon after the doctor left the house for medicine, and the son Thomas entered the room. "Thank God, Tom," said Arnold, "for giving me this pain; I have suffered so little pain in my life, that I feel it is very good for me; now God has given it to me, and I do so thank Him for it."
His son said, "I wish, dear papa, we had you at Fox How." He made no reply, but smiled tenderly upon the boy and his mother.