For whom did Jesus taste death?
Hebrews 2:9

But we do see Him who has been made for a little while lower than the angels, namely, Jesus,
because of the suffering of death crowned with glory and honor, that by the grace of God He might
taste death for everyone.

He triumphed over the grave and rose victorious in the strife for those he came to save. "For those he came to save." These words seem to signal that the writer of this hymn believes that Christ had a design to really save a particular group of people by his death. He triumphed over the grave for those he came to save. It sounds like there are some he came to save, and that for these the grave is defeated and eternal life is given