So, after giving his praise to the Lord in the first five verses of this psalm, David now turns to expressing his confidence in verses 6 through 10.
In particular, David’s confidence seems to be that he has been upright and sought God’s will generally. In other words, he’s on God’s side. He’s interested in God’s interest.
Now – before we get into this section – I want to note that we see the next few verses of this psalm being referenced in Hebrews chapter 10. But before we try to explain how this psalm applies to Christ – as Hebrews 10 indicates that it does – I think we’d do well to think of how these verses applied to David in the original context.
So, let’s do that.
6 Sacrifice and offering thou didst not desire;
mine ears hast thou opened:
burnt offering and sin offering hast thou not required.
So, David is saying that God didn’t desire or require sacrifices. And then he follows that statement up by saying that God has opened or literally dug his ears. God has helped him to understand this truth: that God was never all that interested in sacrifices.
Now, this is overstated – isn’t it? Because – did God desire sacrifice and offering in the Old Testament? Well, yes, of course he did. You can’t avoid the fact that God desired and required his Old Testament people to do these things. So, what is David saying when he says that God doesn’t desire them?
He’s overstating for emphasis. He’s stating what God through many of his prophets would say throughout Old Testament history. Namely, if sacrifice is carried out in deed only and not with the heart engaged, it’s worthless. When God weighs the importance of obedience and sacrifice – he wants both – but ultimately he will not accept the sacrifice without the obedience.
And so, David states that in terms of God not requiring sacrifice.
But God does demand obedience. And so, that’s what David turns to in verses 7 and 8.
7 Then said I, Lo, I come:
in the volume of the book it is written of me,8 I delight to do thy will, O my God:
yea, thy law is within my heart.
Now, let me point out that the word translated in verse 8 as delight is the same Hebrew word that’s translated desire in verse 6. So, David says basically that God doesn’t delight in sacrifice. But David delights to do God’s will. And that will consists of more than just sacrifice. It has to do with God’s law – God’s instructions. Obeying God’s total multifaceted will.
Now, it’s possible that David when he mentions being written of in the volume of the book that he’s speaking of the rules concerning the Israelite king and what he was supposed to do. He was supposed to be a native-born Israelite – according to the Law. He was supposed to not bring the people back to Egypt or multiply horses or multiply wives. He was supposed to take God’s Law – which David is delighting to do here in verse 8 – and he was supposed to write out a copy for himself.
And if David was doing these things, then this psalm would probably be pretty early in his kingship – before he did start multiplying wives to himself.
So, that’s what this part of Psalm 40 likely means for David himself.
But now let’s consider what Hebrew 10 says about this. (Click that link to see that discussion – then come back here!)
…OK, welcome back!
Now, the next two verses in Psalm 40 end David’s section of confidence.
And in these two verses, David repeatedly speaks of God’s righteousness and how David has been proclaiming that righteousness in the midst of a great number of people.
9 I have preached righteousness in the great congregation:
lo, I have not refrained my lips, O LORD, thou knowest.10 I have not hid thy righteousness within my heart;
I have declared thy faithfulness and thy salvation:
I have not concealed thy lovingkindness and thy truth from the great congregation.
And whatever else this great congregation might have been, we are now part of that group in a way. We are hearing about God’s righteous acts – his justice to David. We’re hearing David extolling God’s faithfulness and salvation. And we’re just the latest group to do this in the last 3,000 or so years since David authored this psalm. And we – and everyone who’s read Psalm 40 – can bear witness to the fact that David has done this.
So, there’s David’s confidence. He’s gone beyond mere sacrifice to actually obeying God’s will. He has declared boldly God’s character and actions. He is on the Lord’s side.
Explaining The Book 