At the Disruption, Keith sided with the Free Church and continued to minister to a congregation at St Cyrus and to publish works on biblical prophecy.

I remember him saying, that what led to his writing his book on The Evidence of Prophecy was a conversation with a gentleman in the country town of Stonehaven, who laid great stress on Hume’s argument against miracles.

He set himself with great diligence to collect facts bearing on these, reading books of travel, and twice paying visits to the Holy Land.

[5]Keith is probably best remembered for his book, Evidence of the Truth of the Christian Religion Derived from the Literal Fulfillment of Prophecy, which has gone through numerous revisions and many editions.

It was on his return from the mission on behalf of the Jews, on which he had been sent by the Church of Scotland, that he was seized with serious illness in a hotel at Pest, where Miss Pardoe, author of The City of the Sultan, happened to be staying.

Miss Pardoe was on friendly terms with the archduchess, Maria Dorothea, a Princess of the Wurtemberg family (Protestant), wife of the Viceroy of Hungary, an Austrian archduke, and mother of the Queen of the Belgians.

This good lady had been praying earnestly that God would send some one to direct her how she might be useful to the people of Hungary, and when she heard of Dr. Keith, it occurred to her that he had been sent to Pest in answer to her prayers.

Then followed that splendid mission, of which Dr. John Duncan, the celebrated Christian philosopher, was the animating spirit, with men like Robert Smith,[11][12] William Wingate,[13][12] W. O. Allan and others as coadjutors; which bore such fruits as Adolph Saphir and Alfred Edersheim; which, after being suppressed, still flourishes under Dr. Andrew Moody; which in Duncan’s time drew to him rabbis and priests, men of all creeds; and on which there came such a blessing from Heaven as has never been equalled in any of our Jewish missions.

[15] They remained in Syria for five months, and travelled in different directions above a thousand miles, and along the coast from Gaza to Suedia, at the mouth of the Orontes.

Dr. George Keith was the first to take daguerreotype views of scenes in Syria, from which the illustrations are given in prophecies relating to the restoration of the Jews to edition of the Evidences.

But none of his works reached the popularity of the "Evidences," of which Thomas Chalmers said that "it is recognised in our halls of theology as holding a high place in sacred literature, and it is found in almost every home, and known as a household word throughout the land.