Romans 8:14 For as many as are led by the Spirit of God, they are the sons of God. 8:16 The Spirit itself beareth witness with our spirit, that we are the children of God:
Proverbs 20:27 The spirit of man is the candle of the LORD, searching all the inward parts of the belly. 
Children of God can expect to be led by the Spirit of God. Another translation of Proverbs 20:27 reads; "The spirit of man is the lamp of the Lord......." Had this verse been written today it might have read, " The spirit of man is the light bulb of the Lord"..
What it means is this: God will enlighten us--He will guide us--through our spirits. Many times, however we seek guidance by means other than the way God said and when we do,we get into trouble. We sometimes judge how God is leading by what our physical senses tell us. But nowhere does God say that God will guide us through our physical senses. Too often we look at things from a mental standpoint and endeavour to reason out things. But nowhere does the Bible say God will guide us through our mentality. The Bible does not say that the body of man is the candle of the Lord, nor that the mind of man is the candle of the Lord. It says that the spirit of man is the candle of the Lord (Prov.20:27).