Maybe Kalama Sutta may help.
Please read the whole sutra at www.accesstoinsight.org/tipitaka/an/an03/an03.065.than.html
A very short excerpt (please read the whole sutra!)
..."Of course you are uncertain,
Kalamas. Of course you are in doubt. When there are reasons for
doubt, uncertainty is born. So in this case, Kalamas, don't go by
reports, by legends, by traditions, by scripture, by logical
conjecture, by inference, by analogies, by agreement through
pondering views, by probability, or by the thought, 'This
contemplative is our teacher.' When you know for yourselves that,
'These qualities are unskillful; these qualities are blameworthy;
these qualities are criticized by the wise; these qualities, when
adopted & carried out, lead to harm & to suffering' then
you should abandon them.
"What do you think, Kalamas? When greed arises in a person, does it
arise for welfare or for harm?"
"For harm, lord."
"And this greedy person, overcome by greed, his mind possessed by
greed, kills living beings, takes what is not given, goes after
another person's wife, tells lies, and induces others to do
likewise, all of which is for long-term harm &
suffering."
"Yes, lord."
"Now, what do you think, Kalamas? When aversion arises in a person,
does it arise for welfare or for harm?"
"For harm, lord."
"And this aversive person, overcome by aversion, his mind possessed
by aversion, kills living beings, takes what is not given, goes
after another person's wife, tells lies, and induces others to do
likewise, all of which is for long-term harm &
suffering."
"Yes, lord."
"Now, what do you think, Kalamas? When delusion arises in a person,
does it arise for welfare or for harm?"
"For harm, lord."
"And this deluded person, overcome by delusion, his mind possessed
by delusion, kills living beings, takes what is not given, goes
after another person's wife, tells lies, and induces others to do
likewise, all of which is for long-term harm &
suffering."
"Yes, lord."
"So what do you think, Kalamas: Are these qualities skillful or
unskillful?"
"Unskillful, lord."
"Blameworthy or blameless?"
"Blameworthy, lord."
"Criticized by the wise or praised by the wise?"
"Criticized by the wise, lord."
"When adopted & carried out, do they lead to harm & to
suffering, or not?"
"When adopted & carried out, they lead to harm & to
suffering. That is how it appears to us."
"So, as I said, Kalamas: 'Don't go by reports, by legends, by
traditions, by scripture, by logical conjecture, by inference, by
analogies, by agreement through pondering views, by probability, or
by the thought, "This contemplative is our teacher." When you know
for yourselves that, "These qualities are unskillful; these
qualities are blameworthy; these qualities are criticized by the
wise; these qualities, when adopted & carried out, lead to harm
& to suffering" then you should abandon them.' Thus was it
said. And in reference to this was it said.
"Now, Kalamas, don't go by reports, by legends, by traditions, by
scripture, by logical conjecture, by inference, by analogies, by
agreement through pondering views, by probability, or by the
thought, 'This contemplative is our teacher.' When you know for
yourselves that, 'These qualities are skillful; these qualities are
blameless; these qualities are praised by the wise; these
qualities, when adopted & carried out, lead to welfare & to
happiness' then you should enter & remain in
them...