Mercedes de Jesus Molina was beatified by Saint John Paul II during his pastoral visit to Ecuador on February 1st, 1985, in Guayaquil. On that occasion, the Holy Father established her liturgical feast day on June 12th. During the 137 Plenary Assembly of Bishops on April 24th, 2015, the Episcopal Conference of Ecuador declared her the patron saint of Ecuadorian missionaries "ad gentes."

Mercedes was born in the province of Los Rios in Guayaquil (Ecuador) on February 20th, 1828, filling the house of her parents, Miguel Molina and Rosa Ayala, with love and joy. Unfortunately, she lost them very early in life: her father passed away when she was two years old, and her mother when she was fifteen. She was then entrusted to her older sister, Maria, and moved to Guayaquil, where she could benefit from all the comforts of her great inheritance. Early on, Mercedes fell in love: a young man was fascinated by her beauty that emanated gentleness and purity, and asked her to marry him. One day, however, during a walk with her boyfriend's family, Mercedes fell off her horse and broke her arm. During rehabilitation, she was contemplating Jesus on the way to Calvary and decided to break her conjugal promise, despite the approaching of her wedding day. From that moment on, she decided that she would love and dedicate her life to God alone. Mercedes was no longer the same; other interests found a place in her heart, the same interests of God. She began a life of penance, mortification and fasting. Although she was still dressed with luxurious clothes, she started wearing penitential instruments on her body. Guided by a spiritual director, God manifested Himself many times through visions and locutions during those years. Mercedes finally left the comfort of her sister's house, stripping herself of all her possessions, money, jewels and precious clothing. She entered the Recogidas house in Guayaquil, humbly accepting a chicken coop as a room, and became a tender mother to the orphaned girls, whose hearts she won very quickly. In 1870, the Jesuit Fathers invited her on a mission to eastern Ecuador. Mercedes was so poor that to undertake the journey for her missionary work and for her survival, she had to beg on the streets of Guayaquil. She went through arduous and impervious paths, where the mule on which she was traveling fell on her several times, fortunately without ever hurting her, and she often experienced the cold and loneliness of the night. The strong rivers of the Ecuadorian Amazon threatened to interrupt her journey several times, but thankfully none of these extreme experiences managed to extinguish the fire for the mission that burned in her heart. She was the first Ecuadorian woman to enter this area of the jungle and quickly became a consolation for the Shuar tribe, healing their material wounds and bringing them spiritual consolation. Due to a smallpox epidemic, the health of the missionary fathers deteriorated to such an extent that they were forced to abandon the mission, leaving Mercedes alone with two of her companions. A few months later, the Bishop of Cuenca asked them to leave the mission as well, but Mercedes did not intend to ever abandon her "patients" and asked to remain in the mission until the emergency had been overcome. Without losing the joy of announcing the Good News in all circumstances, when the Shuar overcame the smallpox epidemic, Mercedes went to Cuenca and founded an orphanage there. After three years, she went to Riobamba where on April 14th, 1873, she founded the first Ecuadorian women's religious congregation under the name of Saint Marian Institute of Jesus, taking her vows. On June 12th, 1883, Mercedes was welcomed into the kingdom of Heaven by the Lord.

Mercedes experienced the devastation and pain of the war between the tribes of Mendez and Gualaquiza, facing alongside the Shuar tribe the scourge of smallpox that decimated the population. She treated the sick with gentleness and tenderness inside an improvised hospital tent, and remained close to the patients throughout the course of the epidemic: with the Word she animated, with her hands she cured, and with her heart she loved.