to 'believe' is to respond to God's revelation with affirmation. Believing starts with God; faith comes by hearing and hearing by the word of God. There can be no 'faith' without God's personal utterance. We live by every word 'that is proceeding out of the mouth of God'. Our words are voiced by our breath; God word is voiced by His breath (Spirit). When there is no breath there is no voice and no possibility of hearing.God has His different ways of 'speaking' but we can only respond when He has done so. This is how Christ expresses the process of faith...“He that hath received his witness hath set his seal to this, that God is true. For he whom God hath sent speaketh the words of God: for he giveth not the Spirit by measure. The Father loveth the Son, and hath given all things into his hand. He that believeth on the Son hath eternal life; but he that obeyeth not the Son shall not see life, but the wrath of God abideth on him.” (John 3:33-36, ASV) I have opted for the ASV to emphasise the 'witness'. Putting our seal to a thing is the ancient world's equivalent of 'signing it'. We agree with what has been written and we put our authentication sign on it. There is a powerful Bible thread on this whole matter of 'sealing'. The king's seal carried all the king's authority and was backed up by all his resources. Our 'receiving of His witness' has to be 'sealed' personally by us. We have read the document and we put our whole life behind it by adding our seal.In the metaphor here, God has spoken in the person of Christ, and to believe it to put my whole confidence and backing to that statement. It is an 'amen' that gathers up all my being.There is another aspect of truth revealed earlier in John (and John is one of the best places to go to understand 'believing). “Now when he was in Jerusalem at the passover, during the feast, many believed on his name, beholding his signs which he did. But Jesus did not trust himself unto them, for that he knew all men, and because he needed not that any one should bear witness concerning man; for he himself knew what was in man.” (John 2:23-25, ASV) Again I have gone with the ASV because of the continuing link with 'witness' and because it brings out a different aspect of the truth found in the KJV.The words underlined above are the same word in the original. It is the Greek word 'pisteuo' which is translated by two different English words. This is instructive. They put their 'faith' in Him because of the miracles but He did not put His 'faith' in them because He knew what was in man. There is a 'faith' in Christ which is founded on His miracles. It can be a step in the right direction but it is not what He is looking for. He cannot build or trust that kind of faith. The purpose of John's gospel is “But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name.” (John 20:31, KJV) This is not faith in what He can do, but faith in who He is. Upon this faith He can build...“And Simon Peter answered and said, Thou art the Christ, the Son of the living God. And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven. And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.” (Matt. 16:16-18, KJV)This is Peter's faith, not in what He can do, but in who He is.Faith, ultimately, must be in the person. “And he believed in the LORD; and he counted it to him for righteousness.” (Gen. 15:6, KJV) Of course, Abraham believed what God said, but he believed it because God said it.