Vidvad rudhi means conventional meaning of a word or act from the perspective of an enlightened soul. So if you find people fighting over religion that is because they interpret their scripture in a sectarian and narrow way. Such narrow interpretations are from unenlightened people or called ajnana rudhi.
Unenlightened people with sentimental faith most often than not engage in sectarian discrimination. A true lover of God and genuinely enlightened soul does not make such distinction. There are also unenlightened people with sentimental faith who dilute the sacred scriptures and project their own selfish interpretations. To put it differently, you have unenlightened people who are either fanatic about their God or people who dilute the existence of a personal God to make it universally appealing.
Truly enlightened souls, rather, speak categorically about God, God's will and our duty towards God without dilution or tone of fanaticism. They preach about God in such a way that it is universally applicable to all nationalities, class, and religion and at the same time maintain the integrity of a personal Supreme Being. Such a soul who can speak the essence of all great scriptures is truly enlightened and messenger of God.
"Perhaps you have marked it in my preaching work that I love Lord Jesus Christ as good as Krishna; because He rendered the greatest service to Krishna according to time circumstances and society in which He appeared Similarly Hajrat Mohammed and Lord Buddha also rendered greatest service to the human society according to circumstances"
- Srila Prabhupada - Letter to Kirtananda April 7 1967