Sunan Abi Da'ud

Narrated Abu Hurairah: The Prophet (sal Allaahu alayhi wa sallam ) as saying : Be on your guard against two things which provoke cursing. They (the hearers) said : Prophet of Allaah ( sal Allaahu alayhi wa sallam), what are these things which provoke cursing: easing in the watering places and on the thoroughfares, and in the shade (of the tree)(where they take shelter and rest).