Verse 4

مَـٰلِكِ يَوْمِ ٱلدِّينِ

Master of the Day of Judgement.

The Master (Malik) is the one who possesses the attributes o f sovereignty, one o f the implications o f which is that He enjoins and forbids, rewards and punishes, and controls His subjects in all ways. This sovereignty is connected to the Day o f Judgement, which is the Day o f Resurrection, the day on which people will be judged on the basis o f their deeds, both good and bad. On that day, His perfect sovereignty, justice and wisdom will become completely clear to His creation, and they will realise that created beings have no sovereignty at all. On that day, kings and subjects, slaves and free, will all be equal and will submit fully to His might, awaiting the reckoning, hoping for His reward and fearing His punishment. Hence this day is singled out for mention; otherwise, He is the Master o f the Day o f Judgement and o f all other days.