Ash Wednesday marks the beginning of Lent — the forty-day season of penitence, fasting, and prayer in preparation for Easter. The forty days (not counting Sundays, which are never fast days) recall Christ's forty-day fast in the wilderness (Matthew 4:1–2, Luke 4:1–2), as well as the forty days of Moses on Sinai (Exodus 34:28) and Elijah's journey to Horeb (1 Kings 19:8). The Lenten fast itself is ancient: the Council of Nicaea (325, Canon 5) references a pre-Easter penitential period as an already-established institution, and by the late fourth century a forty-day fast before Easter was observed across both East and West, though the method of counting varied. The specific association of the fast's opening day with ashes developed in the Western church. The use of ashes as a sign of penitence is deeply rooted in the Old Testament: Job repented 'in dust and ashes' (Job 42:6), Mordecai covered himself in sackcloth and ashes (Esther 4:1), and Daniel prayed 'with fasting and sackcloth and ashes' (Daniel 9:3). The prophet Joel's call — 'rend your hearts and not your garments' (Joel 2:13) — is the appointed Old Testament reading for the day and its theological keynote. The imposition of ashes on the heads of public penitents is attested in the Roman Rite from the seventh century. The Gelasian Sacramentary includes prayers for the penitential rite at the start of Lent, and the practice of marking penitents with ashes before their exclusion from the congregation during Lent is documented in Carolingian sources. By the tenth or eleventh century, the rite was extended from public penitents to the whole congregation — a development that reflects the Lenten theology of universal need for repentance. The words spoken at imposition, 'Remember that you are dust, and to dust you shall return' (Genesis 3:19), connect Ash Wednesday to the deepest stratum of biblical anthropology: the mortality that entered through the Fall and the dust from which humanity was fashioned.

The Ash Wednesday liturgy carries a remarkable pastoral directness. The BCP 2019 opens with an 'Invitation to a Holy Lent' that recounts the early Church's Lenten practices — preparation of catechumens for baptism and reconciliation of notorious sinners — and then applies them to the whole congregation: 'I invite you, therefore, in the name of the Church, to the observance of a holy Lent.' The imposition of ashes is understood as occurring in the same sign as baptism: the forehead marked with ash in the shape of the Cross echoes the baptismal signing, but now with the dust of mortality rather than the water of new life. The BCP's introductory essay makes this connection explicit. The day is, with Good Friday, one of only two days the BCP appoints for total abstinence and fasting — a distinction that underscores its severity. The Litany of Penitence, a corporate confession expanding on the General Confession, is proper to Ash Wednesday and draws the congregation into specific acknowledgment of sin under multiple categories. The tradition of 'giving up something for Lent' — now often accompanied by 'taking on' a discipline of prayer or service — descends from the ancient Lenten fast, though in significantly softened form. The Eastern churches begin their Great Lent on Clean Monday rather than Wednesday, and do not practice the imposition of ashes, making Ash Wednesday a distinctly Western observance. The Anglican tradition inherited it at the Reformation: the 1549 BCP included a 'Commination against Sinners' for Ash Wednesday that was gradually softened in later editions, and the imposition of ashes, dropped in 1552, was restored in the twentieth century and is now standard in ACNA practice. The custom of burning the previous year's palm branches to produce the ashes — well established by the medieval period — creates a beautiful liturgical cycle linking Palm Sunday and Ash Wednesday.

The historical David is almost irrecoverable behind the layers of Welsh hagiographic tradition. Rhygyfarch's Life of St. David, written around 1094 to defend the independence of the Welsh church against Norman encroachments, is the earliest surviving biography and was composed roughly five hundred years after David's death.

According to Rhygyfarch, David was born the son of a chieftain named Sant and a woman named Non. He was educated at a monastery and became a priest, then founded a monastic community at Menevia (Mynyw) on the western tip of Pembrokeshire. The community practiced an extreme form of Celtic monasticism: the monks ate only bread, vegetables, and salt with water; they performed heavy manual labor; they spent their evenings in prayer, reading, and writing; and they used no animals for agricultural work.

David is traditionally said to have attended the Synod of Brefi, where he preached against Pelagianism — the ground reportedly rose beneath him so that all could hear — and was subsequently acknowledged as archbishop of Wales. He is credited with founding or inspiring numerous churches across South Wales and beyond.

David died around 601. His last words, according to Rhygyfarch, were 'Be joyful, brothers and sisters. Keep your faith, and do the little things that you have seen and heard with me.' The phrase 'Gwnewch y pethau bychain' — 'Do the little things' — has become the most famous saying associated with any Welsh saint.

David is the subject of the most extensive Welsh hagiographic tradition. Rhygyfarch's Life records miracles, divine visions, and spiritual teachings. David is presented as extraordinarily ascetic, possessing miraculous powers, establishing monasteries with miraculous speed, and converting pagan populations. He is credited with pilgrimage to Rome and papal recognition, and with various miracles of healing and divine intervention.