The disturbing creative spirit

How do you get the spirit of Christian ecumenism into a large glass window?
Earlier this week I spent a fascinating hour and a half with Nicholas Perrin, one of the artists presenting a stained glass window project for a new glass wall to be part of the renovated main hall in the ecumenical centre in Geneva.
Although I am quite creative, I've never had to try and verbalise theological and ecumenical ideas in a way that may help artists conceive their work. Nicholas showed me coloured sketches and ideas that he and his two colleagues had begun to work on. It was challenging to not react immediately and say - I like that, don't like that, not sure about this - but rather to try and think about what the task was, explain some of the religious background and offer encouragement.
I think at one point I said I thought one of the sketches was a little bit too well-behaved and that the colours needed movement, disturbance and spirit.
After talking with him I realised that the problem with my own artistic ideas is that I know what I want to try and do but my skill level is far removed from what I'd like to create. The creative process, even for the much more skilled than me, is one of discipline and application but also of letting go and trusting to intuition and spirit.
Reflecting on that says something to me about discipline and intuition in spirituality. Prayer needs colour and imagination but it also needs discipline and frameworks.