The articles of impeachment were legislation.
https://www.congress.gov/bill/117th-congress/house-resolution/24/textConviction on the impeachment, which required a 2/3 vote in the affirmative, was only part of the Resolution.
The rest of the issues only required a simple majority.
Wherefore, Donald John Trump, by such conduct, has demonstrated that he will remain a threat to national security, democracy, and the Constitution if allowed to remain in office, and has acted in a manner grossly incompatible with self-governance and the rule of law. Donald John Trump thus warrants impeachment and trial, removal from office, and disqualification to hold and enjoy any office of honor, trust, or profit under the United States.