Weiss studied under his father and received semicha (rabbinic ordination) from the Munkatcher Rebbe, Chaim Elazar Shapiro.

Weiss was the Av Beth Din (chief judge of a rabbinical court) in Grosswardein, Romania, before World War II.

When Grosswardein was ceded to Hungary as a result of the Vienna Award he fled to Romania in 1944, where his wife died of an illness.

Weiss wrote a ten-volume set of responsa, Minchas Yitzchak, discussing many contemporary technological, social, and economic issues.

In a section entitled Pirsumei Nissa ("publicising of the miracle") Weiss recorded the extreme ordeals that he experienced in the Second World War.