Catherine Kosic was born of Orthodox parents in the country of Montenegro (Yugoslavia) in 1493. As a young girl she was a shepherdess, but wishing to follow Christ more closely she embraced the solitary life, assumed the habit of a Dominican Tertiary and took the name Hosanna. She spent her life in contemplation and prayer for the salvation of the world and became a counselor for many people. She died on April 27, 1565. Blessed Hosanna is invoked especially for church unity.

  In the earliest centuries all vestments were white – the white of baptismal purity and of the robes worn by the armies of the redeemed in the Apocalypse, washed white in the blood of the Lamb. As the Church grew secure enough to be able to plan her liturgy, she began to use colour so that our sense of sight could deepen our experience of the mysteries of salvation, just as incense recruits our sense of smell and music that of hearing. Over the centuries various schemes of colour for feasts and seasons were worked out, and it is only as late as the 19th century that they were harmonized into their present form.