It was narrated on the authority of Abu Salamah that a dispute arose between him and some other people (about a piece of land). When he told Aisha (the Prophet’s wife) about it, she said, ‘O Abu Salamah! Avoid taking the land unjustly, for the Prophet said:
“Whoever usurps even one span of land of somebody, its depth through the seven earths will be collared to his neck.” (Saheeh Al-Bukhari, ‘Book of Oppression.’)
Salim narrated on the authority of his father that the Prophet said:
“Whoever takes a piece of land of others unjustly, he will sink down the seven earths on the Day of Resurrection.” (Saheeh Al-Bukhari, ‘Book of Oppression.’)
The aforementioned hadith prohibits oppression in general, especially the taking of a piece of land belonging to others unjustly. What might the seven earths refer to?
Studies in geology have proven that the earth is composed of seven zones, identified from the inner to the outer layers as follows:
(1) The Solid Inner Core of Earth: 1.7% of the Earth’s mass; depth of 5,150 – 6,370 kilometers (3,219 – 3,981 miles)
The inner core is solid and unattached to the mantle, suspended in the molten outer core. It is believed to have solidified as a result of pressure-freezing which occurs to most liquids when temperature decreases or pressure increases.
(2) The Liquid Outer core: 30.8% of Earth’s mass; depth of 2,890 – 5,150 kilometers (1,806 – 3,219 miles)
The outer core is a hot, electrically conducting liquid within which convective motion occurs. This conductive layer combines with Earth’s rotation to create a dynamo effect that maintains a system of electrical currents known as the Earth’s magnetic field. It is also responsible for the subtle jerking of Earth’s rotation. This layer is not as dense as pure molten iron, which indicates the presence of lighter elements. Scientists suspect that about 10% of the layer is composed of sulfur and/or oxygen because these elements are abundant in the cosmos and dissolve readily in molten iron.