[2] It was during his administration as Patriarch of Jerusalem that the full significance of the mosaic map found on the church floor in Madaba was understood.

He was occupied with defending the Orthodox faithful in the towns of Husn and Karak from missionaries when, on June 19, 1885, he learned that he had been elected to the see of Antioch.

Realizing the importance of this discovery, Patriarch Gerasimus took action to have the archaeological find properly investigated and preserved.

Gerasimus was also confronted with the activities of the Russian Orthodox Palestinian Society in Palestine that had been ignoring the historical presence of the Patriarchate of Jerusalem.

Their actions led him to increase construction of schools to neutralize the efforts of the Russian society.