They that trust in the LORD shall be as mount Zion, which cannot be removed, but abideth for ever.  As the mountains are round about Jerusalem, so the LORD is round about his people from henceforth even for ever.  Psalms 125:1-2

     That which is here promised the saints is a perpetual preservation of them in that condition wherein they are; both on the part of God, “he is round about them from henceforth even for ever;” and on their parts, “they shall not be removed,”-- that is, from the condition of acceptation with God wherein they are supposed to be, but they shall abide for ever, and continue therein immovable unto the end.  This is a plain promise of their continuance in that condition wherein they are, with their safety from thence, and not a promise of some other good thing provided that they continue in that condition.  Their being compared to mountains, and their stability, which consists in their being and continuing so, will admit no other sense.  As mount Zion abides in its condition, so shall they; and as the mountains about Jerusalem continue, so doth the Lord continue his presence unto them.
     That expression which is used, verse 2, is weighty and full to this purpose, “The LORD is round about his people from hence-forth even forever.”  What can be spoken more fully, more pathetically?  Can any expression of men so set forth the safety of the saints?  The Lord is round about them, not to save them from this or that incursion, but from all; not from one or two evils, but from every one whereby they are or may be
assaulted.  He is with them, and round about them on every side that no evil shall come nigh them.  It is a most full expression of universal preservation, or of God’s keeping his saints in his love and favour, upon all accounts whatsoever; and that not for a season only, but it is “henceforth,” from his giving this promise unto their souls in particular, and their receiving of it, throughout all generations, ”even for ever.”
                                                                                                                                            John Owen