More than 300 pro-Israel activists met their MPs to voice concerns during the Zionist Federation's annual Parliamentary lobby day.
They expressed their fears over rising extremism on campuses and attacks on Christian communities in the Middle East during sessions with parliamentarians last week.
A training session for lobbyists was led by ZF president Eric Moonman and Jacob Vince of Christian Friends of Israel.
Around 100 MPs, including Sir Alan Beith, Louise Ellman, Lee Scott, Theresa Villiers and Luciana Berger, later met constituents for private meetings.
Alan Aziz, ZF chief executive, said: "This was the most successful lobby of its type and we urge all our supporters to exercise their rights as constituency members everywhere to raise their concerns relating to Israel with their MPs.
"Don't complain about UK policy if you are not willing to do anything about it."
Chief Rabbi Lord Sacks greeted participants, thanking the Christians for their support for Israel.
Board of Deputies vice president Jerry Lewis encouraged participants to keep their MPs informed about Israel.