The vigil, organised by the Kirklees Imams and Mosques Advisory Board, was held on the steps of Dewsbury Town Hall yesterday afternoon.
Those gathered were told: "This shows solidarity, this shows unity, and this shows that we are all against terrorism whether we are Muslims or non-Muslims.
"We are all human beings concerned about human beings."
Speeches made by faith leaders urged all communities to work together to prevent further atrocities.
The Bishop of Wakefield, the Rt Revd Tony Robinson, said: "I hope that we can all work with the authorities, the politicians, the police; that we can all do our bit, because we must let these people know that it's mindless, it's cruel."
He appealed to anyone considering a copycat attack to think again, saying that human life was sacred.
Imam Aftab Muhaudden al-Azhari told the crowd: "I want to make it clear to everyone that Islam does not stand for any kind of terrorism.
"Anyone who preaches extremism, anyone who is involved in terrorism, anyone who is involved in killing innocent people. They have nothing to do with Islam."
He also offered prayers for the 'brave and fearless' emergency services and all those working to keep people safe.
Their words were welcomed by those who attended, with a number taking to social media to share pictures and videos.
Christine Wood said: "Incredibly moving and well-attended vigil in Dewsbury this evening. This is about hatred, not faith. To paraphrase something I heard earlier, the only way to get out of the darkness is to become a light. Shine on."
Muddasar Ali wrote: "So lovely to see representatives of the different faiths and people of all backgrounds coming together to remember the lives lost and the impact this has on the families of those affected and an emphasis was put on communities to stand steadfast against divisions and hatred.
"The messages of peace that the great prophets preached were reiterated and ultimately gave the same message that we have far more in common than that which divides us."
Isobel Housecroft tweeted: "I'm so proud of our communities. We've proven our unity time and time again - tonight's vigil in Dewsbury was filled with nothing but love."