Surah Qaf 50:34

ٱدْخُلُوهَا بِسَلَـٰمٍ ۖ ذَٰلِكَ يَوْمُ ٱلْخُلُودِ

Enter it in peace. This is the Day of Eternity."

Translation: Saheeh International

Tafsir

It will also be said to the God-fearing ‘Enter it in peace! that is to say secure from every fear or it means enter it with a greeting that is to say greet yourselves and enter. That day in which this entry takes place is the day of immortality’ of everlastingness in Paradise.

Excerpt from Tafsir al-Jalalayn, commentary on 50:34, via Quran.com. The reader has the full commentary and 9 more tafsirs.