School and Military Life
While still very young, Charles was sent to a preparatory school at Richmond and was later entered at the English public school at Winchester. Concerning his future there was never a doubt, since his own inclinations and the example of his forebears clearly indicated a military career. In fact, he entered the Royal Military College, Sandhurst, in 1835 when he was not quite fourteen years of age. In 1846 he is listed as Captain in the First Battalion of Grenadier Guards. Had he remained in the army he would have risen high in the ranks.    

Becoming a Catholic
At this time he began to have serious qualms about his position as a member of the Anglican Church. John Henry Newman had already become a Catholic and other noted intellectuals were on the threshold of Catholicism. He agonised over the decision. He prayed unceasingly for divine light; he fasted often; he studied text-books of theology, both Catholic and Protestant; and still he could not decide. It was during the summer of 1850 that he made the decision and on 15^th August he was received into the Church by Doctor (later Cardinal) Wiseman.    

Entering the Passionists
One of his sisters was horrified by his defection from Anglicanism. “For goodness sake, Charles,” she snapped, “get married as soon as you can or you’ll end up by becoming a monk”. Her words were prophetic for that is what he decided. He announced he was going to become a Passionist. Family and friends were astounded. The “Iron Duke” of Wellington could scarcely believe the news about his  nephew-in-law. Bad enough to become a Catholic but now a ‘monk’! The old Duke respected Charles and his final words were “Well Charles you have been a good soldier, now strive to be a good monk.” But another uncle, the famous General Lygon, did not take the startling news so philosophically. “Good God,” he ranted, “you’ll break my heart. Why do you persist in this madness?” And madness it appeared to not a few of Pakenham’s friends. 

On a Saturday afternoon in May he left his family and friends behind and arrived on horseback at St. Saviour’s Retreat, Broadway, Worcs., to become a Passionist novice and to receive the new name of Brother Paul Mary. In the eyes of those he loved this was a mortal blow struck at the family honour. To think that their Charles should go about “barefooted like a dirty mad mendicant” was almost too much to bear, “ I wish he were dead,” wailed his sister in desperation. But in the seclusion of his Passionist Retreat, Brother Paul Mary was heard to whisper: “How little have I given up for so much.” In spite of indifferent health, he never flinched in the exact observance of all the rules of the Passionist way of life, and the fervour of his extraordinary piety never cooled.   

Ordained a Priest
Bro. Paul Mary continued his studies and was ordained a priest by Most Rev. Dr. Ullathorne at Oscott College, Birmingham, on September 29^th 1855. After his ordination he was transferred to Rome where he was in charge of students, but soon his superiors recalled him to establish the Passionist Retreat at Mount Argus and to become its first Rector in 1856.   

Mount Argus
In 1852 Fr. Vincent Grotti C.P. had asked Archbishop Cullen of Dublin for a site to found a Passionist Monastery. The Archbishop said he would look round but by 1855 suggested Fr. Vincent look himself. In August of that year Fr. Vincent accidentally met Fr. Matthew Collier a curate in Rathmines parish who wondered why the Passionists had no house in Ireland. To Fr. Vincent’s remark that we are looking for one Fr. Matthew said he knew of a house at Mount Argus owned by a widow Mrs. Elizabeth Byrne. In April 1856 Fr. Vincent visited Mrs. Byrne who signalled she was willing to sell. The deal was done and the Passionists got ready to come to Mount Argus.   

Rector of Mount Argus
First Mass was celebrated by Fr. Paul Mary on 15^th August. The front parlour was used. Increasing numbers came to the house so by September Fr. Paul Mary had decided to build a Church. The top story was removed from the three-storied house and a Church that could take 600 people was built jutting out from the side of the house. It was completed and opened on 18^th December and dedicated to Blessed Paul of the Cross. Fr. Paul Mary must have been pleased with the progress.  

Life continued in the new monastery, masses said, confessions heard and sermons preached. Fr. Paul Mary was a well-respected superior by the other religious. He led by example. The religious willingly followed his lead. The day and night round of prayers were strictly adhered to. All traces of luxury vanished. Food was plain and simple. Soup and deserts were dispensed with. Coffee was taken in the morning without sugar, the rest of the day water was drunk. The people of Dublin flocked to this new priest in their midst. They came for confession where they found a very sympathetic ear. They came to listen to his sermons and to his catechism classes. Religious and people recognised someone special in their midst.

Illness and Last Days
In November 1856 Fr. Paul Mary was appointed to preach, with others, the Mission in the Catholic Church in Rathmines. Halfway through the Mission Fr. Paul Mary fell ill. In the language of the day it was described as 'a seizure of the heart'. He returned to Mount Argus but his health was broken. The religious described him as 'dying on his feet'. Through letters his family were aware of his situation and one of his sisters came to visit him. Into the new year of 1857 the best of medical attention was summoned to no avail. Towards the end of February 1857 Fr. Paul Mary was confined to bed and was often unconscious. The end was near and he received the Last Sacraments and passed to his reward on 1^st March. He was 35 years of age. On that day he was to have preached a Charity Sermon in the Jesuit Church, Gardiner St., Dublin, in aid of the Poor Clare Convent, Harold’s Cross. Fr. Ignatius Spencer C.P. took his place and announced “The voice of him who was to have addressed you today shall never again be heard upon this earth,” One who was present on the occasion recorded that “a suppressed wail of grief” was heard throughout the crowded church. Fr. Paul Mary's notes fo the charity sermon are in the Museum in Mount Argus. 

Although he had lived at Mount Argus for only six months, a newspaper correspondent of the day could report with perfect truth that “Dublin mourned over Father Paul Mary with a universal cry of sorrow.” His funeral was attended by thousands of Dubliners, but only two military officers who had once been his comrades in arms turned up. Archbishop Cullen, Archbishop of Dublin, presided at the Funeral Mass attended by priests, religious and people of the Diocese. Fr. Paul Mary's remains were laid to rest in a corner of the Chapel to Blessed Paul of the Cross that he had built. Later, an altar was placed over the grave.