harry...
"Let your conscience be your guide" sounds good but as you alluded, the conscience by itself is a very poor guide. I suspect that the islamic radicals that kill innocent civilians, the palestinians that indiscriminately kill Jewish women and children and even hitler, who exterminated Jews as if they were vermin all had clear consciences.
The conscience is a valid guide only to the extent that it is properly programmed, and for the Christian, the only proper data with which to program the conscience is Scripture, rightly read and understood in context.
The conscience of secular humanism has no guide other than human reasoning, which is notoriously ill qualified to do the job as shown above. I respect one's right to hold such a world view but I do not have to respect the view itself when I know it is wrong. To respect a worldview or religion that I know is wrong is postmodernism -- there is no right or wrong, true or false -- every one of us has his own truth and mine is no better or more valid than yours. Just the newest version of secular humanism, mixed with New Age philosophy.
mlsoft