I recently went to a pilgrimage and made a donation with the trust in Varanasi.
One of my colleague tells me that I can get some relief in my income tax. Please let me know, where to get information about whether donations made to this trust are exempted from income tax and get me some benefit?

Tax Exemption
Yes, donation is tax exemption.
Various types of organizations are exempt from paying tax. Example, Non-Profit organisations, Charitable Clubs, Religious are tax exemption as well. But the exemptions vary, depending upon the type of organization.