Hazrat Moulana Ashraf Ali Thanwi (rahmatullahi 'alaih) once mentioned:

The path of acquiring the love of Allah Ta'ala largely revolves around the amount of adab that one has in his life. It is not compulsory for one to engage in spiritual exercises and exert himself in acts of nafl 'ibaadah, however it is extremely important for one to have adab. Adab is often understood as one showing excessive honour and respect to the pious, kissing their hands and making salaam to them in a humble manner, whereas this is not what adab actually refers to. Rather, adab means that a person ensures at every moment that he does not cause the slightest amount of inconvenience or difficulty to the next person. (Malfoozaat Hakeemul Ummat 3/318)

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