If I regard iniquity in my heart, The Lord will not hear. (66:18)Is that David is speaking of the sins of the heart. The unspoken sins that we all battle with. A sin that Jesus eluded to in Matthew 5 where in His famous Sermon on the Mount where he points out that both murder and adultery in the heart are just as sinful as if you did them for real.
I will go into Your house with burnt offerings;He is going to God with an offering, an action that is taken when one is asking for forgiveness or when one is thankful for a blessing. In this case he says,
I will pay You my vows. (66:13)
If I regard iniquity in my heart, The Lord will not hear. (66:18)In this case David understands that God can read the hearts of men, and unless he is honest and asks forgiveness for his unspoken sins that lay in his heart, his offering and his presence before God is useless, and God would reject his prayer and him. Something the Pharisees and Sadducee's, in their arrogance and self righteousness, refused to see. So God not only rejected their offerings and prayers, but He also rejected them.
thanks- well, when we don’t deal with ‘small’ things like anger- jealousy, inaction, callousness, gossip, etc- that seems to me as though we ‘regard iniquity in our hearts’- the fact that we keep committing them over and over show that we aren’t really serious about abandoning them- we essentially value them more than we do obedience it seems- It seems we are always in a state of regarding iniquity in our hearts-