Radak: I should merit to see the good of the nation that You chose, that they will merit to see the Ge'ulah. Radak (4) - the author says about himself, that Hashem should raise him from his grave with the dead who will be revived at the time of the Ge'ulah.

Malbim: Since he requested "Zachreni Hashem bi'Rtzon Amecha", he explains, to remember me with Your chosen Tzadikim, to see their good due to their good deeds.

Radak: The matter is repeated three times in different words, to strengthen it, like is common.

Malbim: This corresponds to "Pakdeini bi'Yshu'asecha" - to rejoice with them over their happiness and success. Via these two I will merit to rejoice with Your inheritance - since they are Your inheritance, this shows their Kedushah, and Hashem always clings to them. I will rejoice with them due to their good deeds, or amidst their success and Simchah.

Radak #1: To rejoice. This is like "Kodesh Hilulim" (Vayikra 19:24). Chupah is called 'Bei Hilula' ¹ (Kidushin 32b).

Radak #2: Hilul is an expression of praise. Chupah is called 'Beis Hilula', for they praise the Chasan and Kalah. "U'Vsulosav Lo Hulalu" (78:63) - they were not praised at the Chupah. In Yisrael's Simchah, when they will leave Galus, they will be praised over all nations, for Hashem chose them.

Radak: They are Yisrael - "v'Hem Amecha v'Nachalasecha" (Devarim 9:29).