Faithful Heart

1 Kings 2:4
and that the LORD may keep his promise to me: 'If your descendants watch how they live, and if they walk faithfully before me with all their heart and soul, you will never fail to have a man on the throne of Israel.'

In this chapter David dies. First, he spoke to Solomon, giving him first good counsel, and then a revenge list. This verse follows up the counsel with God's promise to David.
It's more of a covenant, or a conditional promise. The conditions are easy enough to read through, and even to think, Too bad, Israel! You could have had it all!
But think about the conditions.
Watch how you live.
Interesting. A sort of call to be observant, to be conscious of your actions and their implications, not sleep-walking.
Walk faithfully before God with all your heart and soul.
Walk means live. Live faithfully. Before God. He's watching, too, watching well below the level of actions and even conscious thoughts.
With all your heart and soul.
Well, there it is. Because God is watching, my faithful walk must come from my heart, must be my one passion.