Q: What is God?
A: God is a Spirit, infinite, eternal, and unchangeable, in his being, wisdom, power, holiness, justice, goodness, and truth.
John 4:24: God is spirit, and those who worship him must worship in spirit and truth.
It is strange to me that the authors of the Westminster Confession of Faith and the shorter and larger catechisms have been criticized over the past 400 years for trying to "define" God. Dr. Sinclair Ferguson has said that the statements made within this section of the confession and catechisms are clear statements of Biblical orthodoxy which no true Christian can contest. Yet, many Christians have taken up issue. They feel as if the Westminster Divines have tried to make the infinite into a finite being that we can understand. That certainly was not their intention, though, and that is seen clearly in the fact that the Westminster Confession of Faith also says that God is "incomprehensible" (Chapter II). Rather, what the authors of the confession and catechisms have done is simply summarized what the Bible has revealed God to be. And it is in no way a complete list of his glorious attributes!
But the importance of this question, I believe, is related to last week's question concerning what the Scriptures principally teach. The Bible overflows with revelations about God's character and nature, and as we pour over the pages of Scripture, our hearts and minds should overflow with love and affection for our great God.
It is Jesus himself who defines God as spirit, and he himself gives the command to worship him in spirit and truth. We should give some consideration to what it means to worship God in spirit and truth. For that, I leave you with the words of Pastor John Piper:
Worship must be vital and real in the heart, and worship must rest on a true perception of God. There must be spirit and there must be truth. . . . Truth without emotion produces dead orthodoxy and a church full (or half-full) of artificial admirers . . . . On the other hand, emotion without truth produces empty frenzy and cultivates shallow people who refuse the discipline of rigorous thought. But true worship comes from people who are deeply emotional and who love deep and sound doctrine. Strong affections for God rooted in truth are the bone and marrow of biblical worship."