In determining the meaning of the expression ‘the substance of the Faith’, it seems right to go back to the act of the Scottish Parliament in 1690 which ratified the Westminster Confession of Faith ‘as the publick and avowed Confession of this Church, containing the summe and substance of the doctrine of the Reformed Churches.’ There the WCF was regarded as containing the sum and substance of some thirty Reformed Confessions, including the Scots Confession, the First and Second Helvetic Confessions. These confessions expressly acknowledged the ancient Catholic Creeds and Conciliar Statements of the Church, the Apostles Creed, the Nicene Creed, the Formulations of Ephesus and Chalcedon, and the so-called ‘Athanasian Creed’, and embodied all their main statements as essential articles of belief. This was true of the WCF which, as James Denney once pointed out, ‘contains everything that is in the Nicene Creed’ (Jesus and the Gospel, p. 39If). That is to say, there was no move away from what the Athanasian Creed and the Second Helvetic Confession called ‘the Catholic Faith’, although the basic articles of faith handed down through the Creeds were set within a confessional frame of distinctively Reformed character. It was inevitable, therefore, that a distinction was made between what Samuel Rutherford called (Due Right Presbyteries, p. 13) ‘a confession dejure, what everyman ought to believe, as the Nicene Creed, and the Creed of Athanasius’, and a wider summation of teaching common to ‘true Reformed Protestant religion’.

Everything about us today tells us that we live in a world which will be increasingly dominated by empirical and theoretic science. This is the world in which the Church lives and proclaims its message about Jesus Christ. It is not an alien world, for it is in this world of space and time that God has planted us. He made the universe and endowed man with gifts to investigate and understand it. Just as he made life to produce itself, so he has made the universe with man as an essential constituent in it, that it may bring forth and articulate knowledge of itself. Regarded in this light the pursuit of science is one of the ways in which man exercises the dominion in the earth which he was given at his creation. That is how, for example, Francis Bacon understood the work of human science, as man's obedience to God. Science is a religious duty, while man as scientist can be spoken of as the priest of creation, whose task it is to interpret the books of nature, to understand the universe in its wonderful structures and harmonies, and to bring it all into orderly articulation, so that it fulfils its proper end as the vast theatre of glory in which the creator is worshipped and praised. Nature itself is dumb, but it is man's part to bring it to word, to be its mouth through which the whole universe gives voice to the glory and majesty of the living God.