[3] He was arrested, briefly imprisoned, and expelled from the newly formed People's Republic of China in 1949 following the Chinese Communist Revolution.
[3] In 1951, Ruiz's Jesuit provincial sent him to Macau, a Portuguese colony along the southern Chinese coast, to recover from his typhoid;[1][3] he would be based there for the rest of his life.
[8][1][3] He used the official Jesuit residence in Macau, which was called Casa Ricci,[9] as a temporary shelter for the mainland Chinese refugees.
[15] He also extended services to the north of the peninsula and Taipa Island to alleviate family poverty and child labor.
[2][13] Ruiz had learned early on from his experiences in China to avoid political involvement, but engage in dialogue, and he advocated this approach among his fellow workers.
[17] Ruiz began by obtaining medical care, food, water, and help with housing, while religious sisters joined his efforts.
[11][20] It is estimated that Father Ruiz worked with more than 8,000 leprosy patients living in 140 leper colonies located throughout China.
[19] Ruiz went on to establish charitable institutions for the elderly, the disabled, and the mentally handicapped, and to educate social workers throughout much of China.
[11] At the same time, Caritas Macau, which was an offshoot of his original work grew by 2014 to become "one of the city’s largest non-government organisations; it operates 34 centres with 800 staff and 500-600 volunteers.
[27] While Caritas Macau worked mainly in the city, Ruiz founded the Ricci Social Service Foundation to foster the widespread work of Casa Ricci Social Services, "to help the people living in the Chinese mainland and the Macao SAR on the margins of poverty and society, ... and contribute to the development of the country as a whole."
[28] On a personal level, Father Ruiz was said to be an ardent fan of Formula One, Real Madrid and Rafael Nadal.