By inaugurating closed retreats in Canada, Delia wanted to offer brief periods of spiritual renewal for the deepening of Christian life ; she also wished to enable young girls to study their vocation in quiet reflection and prayer.

During the summer of 1911, the little house in Outremont got ready to welcome the first group of forty-two persons, but the requests were so numerous that four successive groups were formed during the school holidays.

The closed retreat project rapidly spread throughout Quebec:
Nominingue (1915), Joliette and Rimouski (1919), Quebec (1921), Granby and Chicoutimi (1930), Ste-Marie-de-Beauce (1932), Saint-Jean (1936).
Other centres for spiritual renewal were also opened in Marlborough (U.S.A), Davao (Philippines), Colón (Cuba), Guanshi (Taiwan), to say nothing of the days of recollection organized in different other countries during certain periods of the year.