What a great perspective. This is such an important way round of understanding things, whether you’re ruling a kingdom or leading a ministry or just managing your own life.
1) It was all from God. God had put him in place and given him everything – it wasn’t through David’s effort or merit that he had got where he was (other than, perhaps, the merit of having this kind of attitude in the first place!).
2) The blessing was for others, not for himself: God had exalted his kingdom (I’m not sure who ‘his’ is referring to here – is it David’s kingdom or God’s?), for the sake of the people of Israel. He had given David victory, power and prosperity in order for David to pass the blessing on to his people.
From God, for others. That’s a good way of looking at our blessings, isn’t it?