The reference in this verse is eschatological, and the Good News Translation makes this clear by introducing the words one day (so also Moffatt).

Once again the assumed agent of the passive verb, be set free, must be God. If God is made subject of the process of “setting free,” the phrase from its slavery to decay may be rendered as purpose—for example, “God set free all creation so that it would not decay” or “… so that finally everything would not rot.” In some languages being set free from slavery to decay may be expressed quite idiomatically—for example, “set free so as not to be worm food again.” Slavery to decay is literally “slavery of decay,” but most translators make the meaning of “to” explicit in this context; the New English Bible expresses it as “shackles of mortality.”

Share the glorious freedom is literally “for the freedom of the glory.” In such a context one would normally understand the genitive “of glory” to be equivalent to an adjective “glorious” (so An American Translation*, Moffatt, New American Bible). However, it is possible to understand the phrase “the freedom of the glory” with the meaning “freedom and glory” (Jerusalem Bible; see New English Bible “liberty and splendor”). A number of translators render Paul’s preposition “for” (Good News Translation share) by a verb (“obtain” Revised Standard Version, “enter upon” New English Bible, “enjoy” Jerusalem Bible, “have” An American Translation*). In some languages glorious freedom may be rendered as “to be set free in a wonderful way” or “will be given the wonderful liberty.”

Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on Paul’s Letter to the Romans. (UBS Handbook Series). New York: UBS, 1973. For this and other handbooks for translators see here .