The Sukhmani Sahib is the greatest composition of Guru Arjan Dev Ji
The Sukhmani Sahib has structural unity. It has 24 staves (Salokas), one of which begins each canto. There are 24 cantos, each containing 8 stanzas. Each stanza has ten lines, that is five couplets. There is also the unity of theme: the perfection of man mentally. morally and spiritually.