Makhdum Zayn ud Deen Malabari al Chishti (Allah have mercy on him) said in regards to fard al ayn (absolute essentials) issues of Islam,

‘The states of the heart, one should know the praiseworthy qualities which one must adopt, and the blameworthy qualities which one must avoid.

As for the praiseworthy traits, they include reliance on Allah, sincerity for Him, praise and thankfulness for His blessings, repentance from one’s sins, fear, hope, abstinence, love, patience, pleasure with His decree, and the remembrance of death.

As for the blameworthy traits, they include greed for food and drink, and a dislike of hunger (given its many benefits such as the purity and softness of the heart, humiliation of the lower self, breaking lusts, and the departure of excessive sleep which prevents worship), eagerness for speech regarding what does not benefit one (the tongue has many faults, the most severe of which are backbiting, lying, and excessive joking and praise), anger, envy, stinginess, love of rank, love of the world, arrogance, pride, and showing off.’

The Guidance for the Intelligent