It could of course be inferred from the presence and purpose of the “everlasting fire” in Gehenna and hades. (Unless there is supposed to be another everlasting fire besides the Holy Spirit, our God the consuming fire, Who brings the Father and the Son to the spirits of men; in which case we have more fundamental theological issues to be discussing, since the existence of another everlasting fire aside from YHWH would be cosmological dualism at best.) The fire of Gehenna salts everyone toward being at peace with one another, and is the best of things. (GosMark 9:49-50; where Jesus explains the hope underlying the previous references to the Isaianic fire-judgment prophecies.)
But (as I noted previously) the end of RevJohn illustrates the Son and the Spirit continually reaching out to those who love and practice their sinning after the lake-of-fire judgment and the establishment of the New Jerusalem. Not only does the Spirit exhort them directly to drink freely of the river of life (which flows from the throne of God out the never-closed-gates of the city) and wash their robes so that they may obtain permission to enter the city and eat of the tree of life (the leaves of which are for the healing of the nations), but the river of life (and the tree, too, if I recall correctly) is a scriptural image for YHWH sending Himself for the rescue of His people and of sinners. (An image expressly adopted by Christ and applied to Himself, reported no less than twice in GosJohn.) Moreover, the church (the bride of Christ) is also exhorted to keep on encouraging the sinners who have not yet repented to repent.
The same concept is also taught in the parable of the 100th sheep: the good Shepherd doesn’t leave the last one outside but persists in finding and bringing it home. The housewife keeps sweeping the floor until she by-God finds that missing coin, too.
Yet again, the same concept is taught in the various Pauline epistles where Christ persists in reigning judgment until all things whether in heaven or on earth or under the earth, are reconciled to Him and in Him to the Father. The imagery used for this concept in 1 Cor 15 is typical of wrath imagery, too, where applicable, and fits extremely well with the verse from Rom 11 where all are shut up into stubborness so that God may have mercy to all.
Or yet again, in the original context of the Isaianic verses with which Christ inaugerated His official ministry in the Nazareth synagogue (as reported in GosLuke), the prisoners who are being set free were put in prison and even already sent to death by God for their sins. But (as in the famous Rachel-weeping-in-Ramah prophecy from Jeremiah) God remembers Ephraim (the rebel son whom He had had to punish to the death) and sorely grieves for the return of the rebel son (the imagery is certainly borrowed from the grief of King David at the death of his rebel son Absalom in Ephraim, hung cursed from a tree, bleeding from his skull and stabbed with a spear!), promising the weeping Rachel whose children have died that He shall restore them to her eventually.
Other respondents may have other verses in mind, of course; these are not likely exhaustive. The RevJohn grand finale is perhaps the most important, though. (It should be noted that the kings of the nations who are bringing in their treasures to the New Jersusalem are always previously described in RevJohn as the most terrible and intransigent rebels, whose bodies Christ scatters to the birds in the final battle at chp 19–but who in the same paragraph shall be continually shepherded by Christ and His rod of iron. The whole scene is an application of the end of the Shepherd’s Psalm, which also features the military verb for a king overrunning an enemy typically with intent to subdue. We do all agree that being run down and overthrown by goodness and mercy is a good thing that we ought to be hoping and praying for as sinners ourselves, right? And so we’re back to all of us being salted by the everlasting fire in Gehenna–our God the consuming fire–so that we may have salt in our hearts and be at peace with one another.)