At Gujrat, he stayed with the governor of the town, Dr Josiah Harlan, an American, and at Wazirabad, with General Avitabile, an Italian serving Ranjit Singh. In Lahore, taking up his abode with General Allard, one of the French officers, Dr Wolff issued proclamations, which were posted in the streets, calling on the nations to turn to the Christ. For this he received from the Sikh sovereign a polite letter of disapprobation in which he said that he had read his proclamations, adding that " such words must neither be said nor heard." The Sikh sovereign who had been following his travels through continual reports, received him in audience in Amritsar and overwhelmed him with his customary wit and banter. He told his visitor that he had been preaching that people should put their trust in the Creator. He asked him why he was not preaching to the English in Hindustan "who have no religion at all." He told Dr Wolff ironically that one way of coming near God was by making an alliance with the British government and that he had ensured this for himself by having a meeting at Ropar with the " Lard Nawab Sahib" (the Governor-General, Lord William Bentinck). Ranjit Singh's native power of persiflage showed to great advantage on this occasion.

Dr Wolff wrote a book entitled The Travels and Adventures of the Rev. Joseph Wolff which was published in London in 1861. His account of the Punjab and its people, however, suffers from a high tone of Occidental superiority and religious bias.

Dr Wolff died at his Somerset Vicarage on 2 May 1862.