If a life of hard work is needed to get you into heaven that's fine. Or if anything less would mean you and your dependants going hungry. But once your basic needs are met then it's irrational not to start spending time on all of the other things that life has to offer.
I feel like drive and energy and work-ethic are great, and you're useless without them. All the same if you have nothing else then you just become enslaved by your need to output more or increase your wealth or whatever, without connecting that to any healthy goal like health or happiness or wellbeing. It's like a cognitive defect, a disability except you're unable to not-do.