What is the ruling on always combining prayers?

Prayer is a great pillar of Islam, and it is the first thing a servant will be judged upon. Delaying it beyond its time is a neglect that warrants a stern warning. Allah Almighty says: "There came after them a generation who neglected prayers and pursued desires; so they are going to meet evil." (Maryam: 59). And Allah Almighty says: "So woe to those who pray, [but] who are heedless of their prayer." (Al-Ma'un: 4-5). It is not permissible to combine all prayers regularly without an excuse, as this is one of the major sins. However, combining prayers is permissible for a legitimate excuse, as clarified by scholars.