We as Christians and believers should enjoy a better life in this world and in the world to come, but most professed believers aren't, why?

Look at vs 17

If you know these things, you are blessed [happy and favored by God] if you put them into practice [and faithfully do them].

We have lots of people throwing off scriptures to prove they are learned and spiritual but when it comes to DOING, they are found wanting.

HAPPY ARE YOU IF YOU DO THEM

So doing qualifies us for the manifestation of God's promises which keeps us happy. If we must see God's hand, we must trust Him enough to obey Him 100%

May God help us