Peace and security in my lifetime

Isaiah 39:1-8
King of Judah, Hezekiah showed everything found in his treasure to the envoys of Babylon. All of these and his discendents will be taken away, and they will become eunuchs in the palace of the king of Babylon.
Hezekiah showed his proud and his wealth.
When Hezekiah heard the prophecy of the Lord through Isaiah, he said "The word of the Lord you have spoken is good." Hezekiah thought "There will be peace and security in his lifetime."
Why?
This event may have been reversed here to provide a lead-in to the following chapters, which focus o Babylon as the world power it later became.
'Peace in my time' was Hezekiah's reaction to the terrible prediction of conquest and captivity. He can not say other words. Isaiah could draw no comfort from the thought.
Hezekiah's recovery is the mercy of the Lord, but his action may lead-in the following diaster of his country. There was selfish mind in Hezekiah.
Even though Hezekiah has peace and security in his life for he followed the commends of the Lord.
How?
All of the propery and health and power is the gift of the Lord, we don't have right to show these to others, what we have to do is praise the Lord gave all of these to us.