According to Rambam,
saying something in order to harm a person,
is a serious violation.
But if the words that are said to harm a person
also happen to be untrue,
this is a more serious violation.
Elazar Cramer:
I agree with Maimonides.
Words can really affect someone,
and so it’s important to avoid saying something
or sharing information that will have a negative effect on someone else,
unless not doing so will have some other major negative consequence.
Halacha 2:
Who is a gossiper (rachil)?
One who collects information
and then goes from person to person, saying:
"This is what so and so said;"
"This is what I heard about so and so."
Even if the statements are true,
they bring about the destruction of the world.
There is a much more serious sin than gossip (rechilut),
which is also included in this prohibition:
evil speech (lashon harah),
that is, saying things that make another person look bad,
even if they are true.
Lashon harah does not refer to lies;
that is referred to as defamation of character (motzi shem ra).
Rather, one who speaks lashon horah
is someone who sits and relates:
"This is what so and so has done;"
"His parents were such and such;"
"This is what I have heard about him,"
telling uncomplimentary things.
Concerning this transgression,
the verse [Psalms 12:4] states:
"May God cut off all guileful lips, the tongues which speak proud things…"
Halacha 5:
[There is no difference] whether one speaks lashon horah
about a person in their presence
or behind their back.
[The statements] of people who say things
which, when passed from one person to another,
will cause harm to a person’s body
or property or will even just annoy
or frighten them are considered as lashon horah.
If such statements were made in the presence of three people,
one may assume that the matter has already become public knowledge.
Thus, if one of those three people repeats the words a second time,
it is not considered lashon horah,
provided his intention was not to spread the matter further and publicize it.