But verses 8 & 9 seem to be key: we must listen and hear what He says to us, and we must fear Him (reverence Him).
Why is this so hard to do? Because we are in a time of terrible warfare, with the enemy being Satan, the world, and our own flesh. But this is no time to lose heart and give up on our loved ones.
Start developing a prayer life and pray for the lost; pray in agony for them; beg your Father in heaven for their souls! Yes, I said, "beg", and rightly so in a persistent and humble way. And remember, He gives good, just like the psalm says!
So it's time to start believing it and living it! The Lord is good, and all that He does is for good!