calligraphy design people were praying

"This new mode was not a matter of script metamorphosing into living
forms which are also readable letters, but of using script to delineate
such forms. Seldom had the flexibility of the Arabic alphabet been so
tested.
This practice established itself only relatively late in
Islamic art, when the taboos outlawing religious iconography had lost
some of their power.
[Zoomorphic calligraphy] developed [..] in Ottoman Turkey, India and Qajar Iran [and] was known as early as 1458."