Baha'u'llah is the one who "shall build up the Temple of the Lord" in Israel.

In the Lawh-i-Hirtík, Bahá'u'lláh addresses Georg David Hardegg in Haifa, asserting that the "appointed time" for the fulfillment of ancient biblical prophecies has arrived. He identifies himself as the one who "shall build up the Temple of the Lord" and describes the Holy Land as being spiritually transformed...

Check Lawh-i-Hirtík (Tablet to Hardegg) here,

https://bahai-library.com/bahaullah_tablet_hardegg_authorized