Final answer:
The Council of Jerusalem declared that all believers are saved through grace, so Gentile believers do not need to adhere to the Mosaic Law for salvation.
Step-by-step explanation:
The Council of Jerusalem declared that all believers are saved through grace. Therefore, Gentile believers will not need to adhere to the Mosaic Law for salvation. This statement is True. During the Council of Jerusalem in the first century CE, the leaders of the early Christian Church discussed whether Gentile believers needed to follow the Mosaic Law, which was the religious law followed by the Jews. The Council concluded that Gentile believers are saved through grace and do not need to adhere to the Mosaic Law for salvation. This decision was significant in the early development of Christianity.