Customs call for the congregation when reciting key prayers (such as Avinu Malkeinu – "Our Father Our King", in many communities), to stand and face the ark, on fasting days, the Ten Days of Repentance between Rosh Hashana and Yom Kippur (also called the High Holidays), and for many piyyutim (poems, songs, etc.)
Many who partake in these customs consider it respectful to stand as long as the ark is open and the Torah is being moved to the reading table (or podium).
However, there is no actual obligation (law) to remain standing when the ark is open, but it is a universally accepted custom.
[5] In ancient times, the cloth wrapped scrolls are believed to have been placed flat within a low wooden box.
Historical records or discoveries point to a variety of exterior designs becoming popular within the Jewish culture of the time.
Archeologists found early Torah arks within the Jewish catacombs in Rome decorated with Pompeian frescoes, paintings, and graffiti.
These texts placed the scrolls inside the ark standing upright, decorated, and wrapped with the appropriate cloth and covers.
A Sephardic synagogue based in Amsterdam (c.1675) contains a baroque style ark, which takes up the entire width of the central hub of the building.
Wood and stone carvers in Eastern Europe began to employ unique local craft designs in synagogue architecture.