Beautiful Hadith is about Prophet Adam AS

Narrated Abu Huraira RA: The Prophet (peace be upon him) said, "Allah created Adam AS, making him 60 cubits tall. When He created him, He said to him, "Go and greet that group of angels, and listen to their reply, for it will be your greeting (salutation) and the greeting (salutations of your offspring." So, Adam AS said (to the angels), As-Salamu Alaikum (i.e. Peace be upon you). The angels said, "As-salamu Alaika wa Rahmatu-l-lahi" (i.e. Peace and Allah's Mercy be upon you). Thus the angels added to Adam's salutation the expression, 'Wa Rahmatu-l-lahi,' Any person who will enter Paradise will resemble Adam AS (in appearance and figure). People have been decreasing in stature since Adam's creation. (Bukhari - Vol. 4, Book 55, Hadith 543)