Kesuvos 104a: When a Tzadik leaves this world, three groups of angels greet him. One group says 'Come in Shalom'; one group says 'He went straightly', and one says "He will come to Shalom, they will rest on their beds."

Shabbos 152b: A parable for this is a king who distributed royal clothing to his servants. The smart ones folded it and put it in a box, and returned it in nice condition. The foolish ones wore it while doing [dirty] work, and returned it dirty. The king was pleased with the former, and put their clothing in the treasury. He incarcerated the latter, and sent their clothing to be laundered. It says about Tzadikim's bodies "Yavo Shalom

Radak: The Chasidim mentioned (verse 1) will have great rest. Death is called Shechivah - "v'Shachavti Im Avosai" (Bereishis 47:30). Even though it can be understood to mean lying in the grave, it will be with tranquility of the Nefesh. Shechivah also implies tranquility - "Lo Shachav Libo" (Koheles 2:23), "v'Orkai Lo Yishkavun" (Iyov 30:17).

Malbim: Hashem says, Anshei Chesed die so they will rest in the world of rest.

Rashi: When there was evil, this one went in his straightness. This is like "Asos Nechochah" (Amos 3:10).

Radak: The Shalom mentioned, the Tzadik will face it when he dies - as opposed to the Resha'im of his generation, who "come close" (3) for judgment on their evil deeds.

Malbim: The Tzadik and Chasid were not lost. Each goes to the place designated to pay his reward.