Modern historians are sceptical of some of its claims: one of Rhygyfarch's aims was to establish some independence for the Welsh church, which had refused the Roman rite until the 8th century and now sought a metropolitan status equal to that of Canterbury (this may apply to the supposed pilgrimage to Jerusalem where he is said to have been anointed as an archbishop by the patriarch).

[6] David is said to have denounced Pelagianism during this incident and he was declared archbishop by popular acclaim according to Rhygyfarch,[7] bringing about the retirement of Dubricius.

The Monastic Rule of David prescribed that monks had to pull the plough themselves without draught animals,[5] and must drink only water and eat only bread with salt and herbs.

King Henry: "I wear it for a memorable honour; for I am Welsh, you know, good countryman".Rhigyfarch counted Glastonbury Abbey among the churches David founded.

One manuscript indicates that a sapphire altar was among the items Henry VIII of England confiscated from the abbey during the Dissolution of the Monasteries a thousand years later.

The Welsh Life of St David gives these as, "Arglwyddi, brodyr, a chwiorydd, Byddwch lawen a chadwch eich ffyd a'ch credd, a gwnewch y petheu bychain a glywsoch ac y welsoch gennyf i.

A mwynhau a gerdaf y fford yd aeth an tadeu idi",[11] which translates as, "Lords, brothers and sisters, Be joyful, and keep your faith and your creed, and do the little things that you have seen me do and heard about.

In 1275 a new shrine was constructed, the ruined base of which remains to this day (see photo), which was originally surmounted by an ornamental wooden canopy with murals of David, Patrick and Denis.

Music for his Liturgy of the Hours has been edited by O. T. Edwards in Matins, Lauds and Vespers for St David's Day: the Medieval Office of the Welsh Patron Saint in National Library of Wales MS 20541 E (Cambridge, 1990).

A broadside ballad published around 1630 claimed that the Welsh wore a leek in their hats to commemorate a battle fought on St David's Day.

David is said to have played a role in spreading Christianity on the continent, inspiring numerous place names in Brittany including Saint-Divy, Saint-Yvi and Landivy.

David's life and teachings have inspired a choral work by Welsh composer Karl Jenkins, Dewi Sant.

It is a seven-movement work best known for the classical crossover series Adiemus, which intersperses movements reflecting the themes of David's last sermon with those drawing from three Psalms.