A brief look at the three type of worshipers in our modern age and even in ages immemorial
1-A group of people worshipped God out of desire for reward;this is the worship of traders.
2-another group worshipppped God out of fear;this is the worship of slaves
3-another group worshiped God out of gratitude;this is the worship of freemen
Even if God had not warned those disobedient to Him of chastisement,it was obligatory by way of gratefulness for his favour that He should not be disobeyed
Be sincere with thy self;to which of the aforementioned group do you belong??

The number 2 is the fear of Damnation