The design for the window is a reflection of the history of the church and represents the sentiment in the following words when discussing its founders, ‘Their faith was strong, their spirit relentless, their sacrifices great’
The church is symbolised in the centre of the window with the circular form and paten or communion plate representing the sacrament of Holy Communion and the bringing together of people. This central motif frames all the other symbols.
The words ‘Faith, Spirit, Sacrifice’ are symbolised by using the dove to represent the Spirit, the cross as a symbol of sacrifice, in Christ’s sacrifice for our salvation, and the symbol of the Jesuits referring to St David Lewis, whom the church is dedicated to, as a symbol of faith in his act of martyrdom. Underneath the cross are root like shapes symbolising the roots of the church’s congregation of Irish families. The roots turn into the cross and behind the cross faded in the background is the shamrock leaf, used by St Patrick as a metaphor for the Holy Trinity. The multicoloured flecks moving to the centre of the window represents the welcome to the Church from other cultures of the world with the daffodil, appearing to the left of the cross, reflecting a new home in Wales. The colour blue as well as being a beautiful colour in glass is also a symbol of faith, truth and reflection.