Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: "I swear by this city" [Surah al-Balad: 1] means "Makkah"; "and you are a dweller in this city" [Surah al-Balad: 2] means "Makkah"; "and by the father and what he begot, We have certainly created man in toil" [Surah al-Balad: 3-4] means "in balance and in an upright stature."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 12359