It depends on your current lifestyle and commitments. At 38 you're still quite young, so im guessing 1.5M is not enough to last you a lifetime, especially if you have a family.

Secondly, sometimes investments require some luck. If you happen to buy at the bottom of the financial crisis in 2009, you would have made a lot of money. But if you quit your job now and manage your money, you may not re-produce this kind of spectacular returns. (Just giving caution given that we do not know how you made the 1M)

Thirdly if i were you, i'll quit the current job and find some other job that i enjoy just to receive some extra income