Agnes Gonxha Bojaxhiu was born on August 26, 1910, in Skopje, then part of the Ottoman Empire (modern-day North Macedonia). Her Albanian Catholic family was deeply religious, and from a young age, Agnes felt a strong call to religious life, particularly to serve as a missionary. At the age of 18, she left home to join the Sisters of Loreto in Rathfarnham, Ireland, a congregation known for its missionary work in India. It was there, in 1928, that she received her religious habit and the name Sister Mary Teresa, after Saint Thérèse of Lisieux, the patroness of missionaries. This initial step marked the beginning of a life wholly consecrated to God and service, a path that would eventually lead her to become one of the most recognized figures of Christian charity in the 20th century.

After a brief novitiate in Ireland, Sister Teresa sailed to India in 1929, arriving in Calcutta (now Kolkata) in 1931. She made her first vows in Darjeeling in 1931 and her final vows in 1937. For nearly two decades, she served as a teacher and later as principal at St. Mary's High School for Girls, run by the Loreto Sisters in Calcutta. The school was situated in a relatively affluent part of the city, and while she dedicated herself to educating young women, the stark poverty outside the convent walls deeply affected her. She often passed through the city's slums, witnessing the immense suffering, disease, and destitution that afflicted countless people, a contrast that would profoundly shape her future mission. Her time as a Loreto sister honed her spiritual discipline and commitment to prayer, preparing her for the radical call that was yet to come.

The pivotal moment in Mother Teresa's life occurred on September 10, 1946, during a train journey from Calcutta to Darjeeling for her annual retreat. She later described this as a "call within a call" – a direct inspiration from Christ to leave the convent and serve Him among the poorest of the poor. This was not merely a desire to help, but a profound spiritual imperative to establish a new religious community dedicated entirely to those who were most destitute, those who were literally dying on the streets. This divine summons, which she kept secret for a time, compelled her to seek permission from her superiors and eventually from the Holy See to embark on this audacious new mission, which would require her to live among and identify with the suffering.

After two years of discernment and persistent petition, Mother Teresa received permission from Pope Pius XII in 1948 to leave the Loreto Sisters and begin her work as an independent nun, wearing the simple white sari with blue borders that would become her iconic habit. She moved into the slums of Calcutta, initially living with the poor, teaching children, and tending to the sick and dying. Her radical approach soon attracted others, and on October 7, 1950, the Missionaries of Charity was officially established as a diocesan congregation. The sisters took vows of poverty, chastity, obedience, and a fourth vow: to give wholehearted free service to the poorest of the poor. Their mission expanded rapidly, establishing homes for the dying, orphanages, schools, and leprosy centers, embodying the Gospel's call to serve "the least of these."

The congregation grew exponentially, attracting vocations from around the world and extending its reach far beyond Calcutta. By the 1960s, Mother Teresa was opening houses across India, and by the 1970s, the Missionaries of Charity had established a presence on every continent, providing care in war zones, disaster areas, and impoverished communities. Her tireless efforts and the visible impact of her work garnered international attention and numerous accolades. In 1979, she was awarded the Nobel Peace Prize for her humanitarian work, accepting it "in the name of the hungry, the naked, the homeless, of the blind, of the lepers, of all those who feel unwanted, unloved, uncared for throughout society." She used the prize money to further her mission, always emphasizing that her work was not merely social service but an expression of Christ's love.

Despite her outward image of unwavering faith and joy, Mother Teresa privately experienced profound spiritual desolation, a "darkness" or "absence of God" that lasted for decades. This period, revealed in her private letters after her death, showed her deep interior suffering, yet she continued her work with extraordinary zeal, seeing it as a participation in Christ's own suffering and abandonment. This hidden struggle underscores her heroic virtue and profound trust in God, even when she felt His absence. Mother Teresa passed away on September 5, 1997, at the age of 87. Her funeral was a state funeral in India, a testament to her global impact. She was beatified by Pope John Paul II in 2003 and canonized by Pope Francis on September 4, 2016, becoming Saint Teresa of Calcutta. Her life remains a powerful witness to radical Christian charity, demonstrating how profound faith can translate into tangible love for the most vulnerable, reflecting the very heart of the Gospel and inspiring countless individuals to live out their faith through service.

The sun beat down relentlessly on the crowded, dusty streets of Calcutta, the air thick with the scent of poverty and despair. Mother Teresa, her slight frame draped in the simple white sari with blue stripes, moved with quiet determination through the teeming lanes. Her eyes, though weary, held a penetrating gaze that saw beyond the squalor to the inherent dignity of every human soul.

One sweltering afternoon, as she navigated a particularly desolate alley, her gaze fell upon a sight that, while tragically common, never failed to pierce her heart. A woman, barely more than a skeleton, lay slumped against a wall, her breath shallow, her body ravaged by disease and neglect. Flies buzzed around her, and passersby hurried past, averting their eyes, accustomed to such suffering.

But Mother Teresa did not pass by. She knelt beside the dying woman, her face etched with profound compassion. Gently, she reached out, not with a grand gesture, but with a simple, tender touch. She cleaned the woman's emaciated body, offering sips of water, and spoke words of comfort and love. With immense effort, she lifted the woman, holding her close, cradling her head against her shoulder as if she were embracing Christ Himself.

As the woman breathed her last in Mother Teresa's arms, a profound peace settled upon her face. Mother Teresa later recounted, "I picked up a person from the street, and she was eaten by worms. I took her to the house. I could feel her presence, and as I was cleaning her, I said, 'You are Christ, and I am serving you.'" This was not a mere act of charity; it was an act of profound faith, a living sacrament where the broken body of the poor became the very body of Christ, deserving of infinite love and reverence. It was this unwavering conviction that fueled her mission and transformed the discarded into the divine, revealing the very heart of the Gospel in action.