The four suspects - Israelis in their 20s - were arrested Saturday, spokesman Micky Rosenfeld said. They are accused of stealing the items from Milan's central synagogue last week and smuggling them to Israel.
The Jewish community of Milan reported the theft on Friday, saying in a statement that a golden key to the ark holding the synagogue's Torah scrolls was taken along with "very precious silver objects," including ornaments for Torah scrolls.
The synagogue's rabbi discovered the theft and reported it to local police.
The stolen objects date to the 1600s and 1700s and have been owned by the Milanese community for centuries, according to the statement.
The community welcomed news of the arrests, saying that "it was a day of celebration for the Milanese community but also for all Italian Jews." The community's president, Roberto Jarach, said everything stolen was recovered and would be brought back to Italy.
The Israeli daily Yediot Ahronot reported that police were tipped off by a Judaica expert in Jerusalem who was consulted on the value of the pieces by a dealer interested in buying them. The expert had already been informed of the theft by the Milan synagogue's rabbi, David Schunnach.
Schunnach told the paper that the men arrived at the synagogue on Jan. 31, presented themselves as tourists and left bags there for safekeeping. Two of them returned the next day, entered the sanctuary, took the items and put them in the bags they had left, departing without anyone noticing the theft, he said.
Synagogues often house precious items used for ritual purposes or for decoration.
Alessandra Rizzo contributed to this report from Rome.