Cnut's actions as a conqueror and his ruthless treatment of the overthrown dynasty had made him uneasy with the Church.
He was already a Christian before he was king—being named Lambert at his baptism—although the Christianization of Scandinavia was not at all complete.
His open relationship with a concubine, Ælfgifu of Northampton, his handfast wife, whom he kept as his northern queen when he wed Emma of Normandy (confusingly also Ælfgifu in Old English), who was kept in the south with an estate in Exeter, was another conflict with Church teaching.
In an effort to reconcile himself with his churchmen, Cnut repaired all the English churches and monasteries that were victims of Viking plunder and refilled their coffers.
He also built new churches and was an earnest patron of monastic communities.
His homeland of Denmark was a Christian nation on the rise, and the desire to enhance the religion was still fresh.
As an example, the first stone church recorded to have been built in Scandinavia was in Roskilde, c. 1027, and its patron was Cnut's sister Estrid.

It is difficult to ascertain whether Cnut's attitude towards the Church derived from deep religious devotion or was merely a means to reinforce his regime's hold on the people.
There is evidence of respect for the pagan religion in his praise poetry, which he was happy enough for his skalds to embellish in Norse mythology, while other Viking leaders were insistent on the rigid observation of the Christian line, like St Olaf.
Yet he also displays the desire for a respectable Christian nationhood within Europe.
In 1018, some sources suggest he was at Canterbury on the return of its Archbishop Lyfing from Rome, to receive letters of exhortation from the Pope.
If this chronology is correct, he probably went from Canterbury to the Witan at Oxford, with Archbishop Wulfstan of York in attendance, to record the event.

His ecumenical gifts were widespread and often exuberant.
Commonly held land was given, along with exemption from taxes as well as relics.
Christ Church was probably given rights at the important port of Sandwich as well as tax exemption, with confirmation in the placement of their charters on the altar, while it got the relics of St Ælfheah, at the displeasure of the people of London.
Another see in the king's favour was Winchester, second only to the Canterbury see in terms of wealth.
New Minster's Liber Vitae records Cnut as a benefactor of the monastery, and the Winchester Cross, with 500 marks of silver and 30 marks of gold, as well as relics of various saints was given to it.
Old Minster was the recipient of a shrine for the relics of St Birinus and the probable confirmation of its privileges.
The monastery at Evesham, with its Abbot Ælfweard purportedly a relative of the king through Ælfgifu the Lady (probably Ælfgifu of Northampton, rather than Queen Emma, also known as Ælfgifu), got the relics of St Wigstan.
Such generosity towards his subjects, which his skalds called destroying treasure, was popular with the English.
Yet it is important to remember that not all Englishmen were in his favour, and the burden of taxation was widely felt.
His attitude towards London's see was clearly not benign.
The monasteries at Ely and Glastonbury were apparently not on good terms either.

Other gifts were also given to his neighbours.
Among these was one to Chartres, of which its bishop wrote: "When we saw the gift that you sent us, we were amazed at your knowledge as well as your faith ... since you, whom we had heard to be a pagan prince, we now know to be not only a Christian, but also a most generous donor to God's churches and servants".
He is known to have sent a psalter and sacramentary made in Peterborough (famous for its illustrations) to Cologne, and a book written in gold, among other gifts, to William the Great of Aquitaine.
This golden book was apparently to support Aquitanian claims of St Martial, patron saint of Aquitaine, as an apostle.
Of some consequence, its recipient was an avid artisan, scholar and devout Christian, and the Abbey of Saint-Martial was
Cnut's actions as a conqueror and his ruthless treatment of the overthrown dynasty had made him uneasy with the Church. He was already a Christian before he was king—being named Lambert at his baptism—although the Christianization of Scandinavia was not at all complete. His open relationship with a concubine, Ælfgifu of Northampton, his handfast wife, whom he kept as his northern queen when he wed Emma of Normandy (confusingly also Ælfgifu in Old English), who was kept in the south with an estate in Exeter, was another conflict with Church teaching. In an effort to reconcile himself with his churchmen, Cnut repaired all the English churches and monasteries that were victims of Viking plunder and refilled their coffers. He also built new churches and was an earnest patron of monastic communities. His homeland of Denmark was a Christian nation on the rise, and the desire to enhance the religion was still fresh. As an example, the first stone church recorded to have been built in Scandinavia was in Roskilde, c. 1027, and its patron was Cnut's sister Estrid.
It is difficult to ascertain whether Cnut's attitude towards the Church derived from deep religious devotion or was merely a means to reinforce his regime's hold on the people. There is evidence of respect for the pagan religion in his praise poetry, which he was happy enough for his skalds to embellish in Norse mythology, while other Viking leaders were insistent on the rigid observation of the Christian line, like St Olaf. Yet he also displays the desire for a respectable Christian nationhood within Europe. In 1018, some sources suggest he was at Canterbury on the return of its Archbishop Lyfing from Rome, to receive letters of exhortation from the Pope. If this chronology is correct, he probably went from Canterbury to the Witan at Oxford, with Archbishop Wulfstan of York in attendance, to record the event.
His ecumenical gifts were widespread and often exuberant. Commonly held land was given, along with exemption from taxes as well as relics. Christ Church was probably given rights at the important port of Sandwich as well as tax exemption, with confirmation in the placement of their charters on the altar, while it got the relics of St Ælfheah, at the displeasure of the people of London. Another see in the king's favour was Winchester, second only to the Canterbury see in terms of wealth. New Minster's Liber Vitae records Cnut as a benefactor of the monastery, and the Winchester Cross, with 500 marks of silver and 30 marks of gold, as well as relics of various saints was given to it. Old Minster was the recipient of a shrine for the relics of St Birinus and the probable confirmation of its privileges. The monastery at Evesham, with its Abbot Ælfweard purportedly a relative of the king through Ælfgifu the Lady (probably Ælfgifu of Northampton, rather than Queen Emma, also known as Ælfgifu), got the relics of St Wigstan. Such generosity towards his subjects, which his skalds called destroying treasure, was popular with the English. Yet it is important to remember that not all Englishmen were in his favour, and the burden of taxation was widely felt. His attitude towards London's see was clearly not benign. The monasteries at Ely and Glastonbury were apparently not on good terms either.
Other gifts were also given to his neighbours. Among these was one to Chartres, of which its bishop wrote: "When we saw the gift that you sent us, we were amazed at your knowledge as well as your faith ... since you, whom we had heard to be a pagan prince, we now know to be not only a Christian, but also a most generous donor to God's churches and servants". He is known to have sent a psalter and sacramentary made in Peterborough (famous for its illustrations) to Cologne, and a book written in gold, among other gifts, to William the Great of Aquitaine. This golden book was apparently to support Aquitanian claims of St Martial, patron saint of Aquitaine, as an apostle. Of some consequence, its recipient was an avid artisan, scholar and devout Christian, and the Abbey of Saint-Martial was 
Cnut the Great