He entered the United States Naval Reserve and became a private practice lawyer, later becoming assistant district attorney of the city of Philadelphia from 1952 to 1954.

He was elected to the Pennsylvania State House of Representatives, serving from 1954 to 1966, rising to the position of majority leader in 1965–1966.

In that role, Representative Eilberg led a legislative veto to override the Attorney General's suspension of deportation of Jagdish Rai Chadha and five others under the Immigration and Nationality Act.

[2] Eilberg lost his 1978 reelection bid, and, three months later, pleaded guilty to conflict of interest charges.

They had a daughter, Amy Eilberg,[4][5] who is the first female rabbi ordained in Conservative Judaism,[6] and a son, William.