Vayikra 22.32
Velo techalelu et-shem kodshi venikdashti betoch beney Yisra'el ani YHVH mekadishechem.
You shall not profane my holy name; but I will be made holy among the children of Yisra'el: I am YHVH who makes you holy.

Again, our actions say a lot about us. Everything we do, has an effect on the way others look at us and the Torah.

If we follow His mitzvot, and act in a kind and just way, other people will see and praise YHVH.

This is what Positive Mitzvot 9 is about.

Mattityahu/Matthew 5:16
In the same way, let your light shine before people, so that they may see the good things you do and praise your Father in heaven.

In contrast, if we act improperly, people will not only criticize us, but also the Name of YHVH.

Romans 2:23-24
You who take such pride in Torah, do you, by disobeying the Torah, dishonor YHVH?— as it says in the Tanakh, "For it is because of you that YHVH’s name is blasphemed by the Goyim."

This is called a "Chillul HaShem" - a desecration of YHVH's name.

1) The first type of Chillul HaShem is when the Jewish religion is challenged.

If an evil nation or person proclaims that Jews are no longer allowed to follow the Torah, obeying such a ruling would be considered a Chillul HaShem.

Our history is full of countless stories of Jews who chose to sacrifice their lives rather than deny their faith.

2) The second type of Chillul HaShem is when a Jew's behavior is irresponsible and disrespectful of Torah and Mitzvot, even if he does not benefit from his actions. This is also a Chillul HaShem.

3) The third type of Chillul HaShem involves an individual who is regarded as a religious person and upholds the Torah.

If this person does something that even seems wrong, other people will point at him and say: "Look at that person who calls himself a religious Jew!"