The teacher did not set anyone up for ridicule and hate by stating that all sin is equal and that all are sinners, including him. He did not state anyone's existence was distasteful or anything similar to that. He likewise did not condemn anyone as equivalent to murderers by virtue of how they were born. Please note, as Nova pointed out, the causes/origins of homosexuality have not been established. Stating it's how they're born is thus opinion.
Definition of bias:
Webster's
b : an inclination of temperament or outlook; especially : a personal and sometimes unreasoned judgment : prejudice
Bias - Wikipedia, the free encyclopediaBias is an inclination to present or hold a partial perspective at the expense of (possibly equally valid) alternatives. Anything biased generally is one-sided, and therefore lacks a neutral point of view.
Have you considered that your stated bias against religion might color your perception of what he's saying?