“But the fearful, and unbelieving, and the abominable, and murderers, and whoremongers, and sorcerers, and idolaters, and all liars, shall have their part in the lake which burneth with fire and brimstone: which is the second death.” – Revelation 21:8

We believe that those who die in their sins when they pass from this life into the next, shall find that second death to be no extinction of existence, but an eternity of sin and of misery, Ah! how can any of us bear to think of this if we feel that we are morally responsible for any one soul that is damned? Yet are we so, I speak but the bare truth, until we have delivered ourselves from that responsibility by faithful earnestness. Is there a Cain here who says, “Am I my brother’s keeper?” I shall not appeal to your most sympathetic soul but leave you to your Judge. But to the Christian I say, “No man liveth to himself.” When you think of a spirit in despair, cast out for ever from the presence of his God and from the glory of his power, may you, friends, be able to say, “Great God, though I understand not Thy ways, for Thy judgments are a great deep; yet I warned the sinner, I admonished him to lay hold on Christ, and if he perished it was not for want of preaching to or for praying over; my warnings and tears were never spared. I did what was in me to prevent his ruin.” Put in that light, we may look at least with some degree of serenity upon the doctrine of divine sovereignty. I must confess that the sovereignty of God is a great mountain whose top we cannot scale. I often marvel at the coldness with which some men talk of the sovereignty of God, as though it were of small concern whether men were lost or saved. They seem to take these things as easily as if they were only talking of blocks of wood, or fields filled with tares. I do not think that we can equitably plead the divine sovereignty as a counterpart to our futile efforts, till we can say, “I have done all that was possible to bring that soul to God, I have prayed over him and wept over him, and now if he perish I must believe that this man wilfully rejected Christ, that his iniquities are upon his own head, and that in him, as a vessel of wrath, God will get glory as well as in vessels of mercy. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/0977.cfm