The first reading is from the book of Proverbs (8:22-31), which is classed as wisdom literature. The section we have for today is a poem spoken by wisdom herself, Sophia in the Greek. The whole passage is chiefly about the presence of wisdom while God was creating. Among the nations surrounding the chosen people there were other collections of what may be called wisdom writing. Here she is an aspect of God before, during and even after the process of creation. In Christian circles this developed and Wisdom came to be identified eventually as one of the three that comprise God – the doctrine of the Trinity; but this took time and is still a mystery. Despite all this theology and doctrine we see in it, the reading is a quite delightful poem.
The second reading is from Paul’s letter to the Romans (5:1-5), the most structured of all his writings. He had had difficulties of various kinds in his life as a Christian, and here he tries to express what he has learnt from this. It is a suitable reading for Trinity Sunday because he explains something of the relationship of God to us Christians. It is through the presence of God in Christ with us in our humanity that we who are enabled to believe, realise our right relationship with God (which is what the word ‘justification’ means in Paul). He wants to ‘boast’ of this, but maybe being proud would be a more appropriate way of saying it. When a believer has hardship one is strengthened and builds up a great hope – if for nothing else, for a share in the glory of God; and this strength is the very Spirit of God within us bringing us a deep peace through it all. Thus our life is involved in the very threeness of God, through Christ and the Spirit.
The third reading is from John’s gospel (16:12-15) which is clear from its style. The words attributed to Jesus express both the unity of Father, Son and Spirit, and also the promise that the understanding of the significance of this threeness will develop through time. It can develop for us as individuals in different ways or areas of our lives; for some it might be in an intellectual way with the use of words and thoughts, but for others in a devotional way as they grow loving Jesus or experiencing His Spirit, and for some it might work out in their practical living like Jesus, living for others and with the energy of God’s Spirit. For the Church as a whole it developed the Creed with its faith in the Trinity, but this doctrine, will always be a mystery, although what is important is not so much any grasp of the meaning, as living out the practical implications of being spirited.
See Jeffs Jottings on the Trinity