Rashi notes that Moshe chastises the Jew who struck his friend using the future tense.
“וַיֹּאמֶר, לָרָשָׁע, לָמָּה תַכֶּה, רֵעֶךָ” – “And he said to the bad one, ‘Why would you strike your friend?'” Shemot 2:13
Among those who are disqualified to testify (פסולי עדות), the Ram”a (Shulchan Aruch: Choshen Mishpat 34) includes one who lifts his hand to hit.
This is remarkable.
One who plans on sinning is not disqualified, whereas, apparently the act of lifting one’s hand to hit someone, in of itself categorizes one as a “rasha”.
This disqualification is Rabbinic, as there are no “Makot” (lashes) given, but one who actually strikes his friend would be pasul Mid’oraisa (R. Akiva Eger) as the lack of Makot is a technicality in that case.
Lesson: Avoid violence. Anger that could lead to violence isn’t too good either.