There is no such thing as a Jewish church. A Jewish house of worship is called a synagogue.
There is no standard item that is above the Holy Ark in a synagogue. Some synagogues put the ner tamid (eternal light) there.
Almost all have a small, unobtrusive light, in a decorative enclosure, hanging on an extended arm,
referred to as the "NAYR tah-MID" = "Constant Light" or "Eternal Light".
Many also have inscribed over the ark the Hebrew words:
"DAH leef-NAY MEE ah-TAH oh-MAYD" ...
"Consider before whom you stand". (Translation is mine, not official.)
The ark is known as the Aron Kodesh (ארון קודש) and it contains the synagogue's Torah scrolls.
We don't know where the ark is and it has never been in a synagogue. It had been in the temple in a room called the Holy of Holies.
ARK
Assuming the questioner is asking where the 10 Statements are located in a synagogue, the answer is that if a synagogue has the 10 Statements on display, they are usually located on or above the ark containing the Torahs at the front of the prayer sanctuary.
The Holy Ark is the place where the Torah scrolls are kept.
There is no single phrase. It depends on the synagogue. In my synagogue, it's the sentence that translates as "Consider before whom you stand." It's a piece of advice from the section of the Mishnah that contains brief quotes and points to ponder from great Judaic sages of the past; the book is subtitled "pir-KAY ah-VOT", or "Ethics of the Fathers".
It is where the Torah scroll is kept.
The Holy Ark in a synagogue may have any appropriate Hebrew quote above it; or it may have none. There's no specific requirement. If there is a particular ark's quotation that you wish for someone on this site to translate, please submit a separate question asking what that phrase (identifying it) means.
To hold the Torah scroll in the synagogue.
Torah scrolls
The Ark in a Synagogue is an intricately decorated cabinet used for storing the Torah scrolls - the Jewish holy scripture. It is placed so that it is facing the city of Jerusalem and is one of the most important standard objects in the Synagogue.
Perhaps you're referring to the 'ark'. The ark is where the Torah scrolls are stored.