Fulgentius, an early church writer, north African bishop, and disciple of Augustine, explains the meaning of God’s will to save all men, namely that it means not all men without exception, but all men without distinction.
Fulgentius, bishop of Ruspe (c. 467-532): For this reason regarding all those whom God wishes to save, we must understand that we do not think anyone can be saved apart from God who wills it. Further, let us not imagine that the will of the omnipotent God either is not fulfilled or is in any way impeded in certain people. For all whom God wishes to save are unquestionably saved, and they cannot be saved unless God wishes them to be saved, and each person whom God does not will to be saved is not saved, since our God “has done all things that he willed.” Therefore, all are saved whom he wishes to be saved, for this salvation is not born of the human will but is supplied by God’s good will. Nevertheless, these “all men” whom God wishes to save include not the entire human race altogether, but rather the totality of those who are to be saved. So the word “all” is mentioned because the divine kindness saves all kinds from among all men, that is, from every race, status, and age, from every language and every region. In all of these people, this message of our Redeemer is fulfilled where he says, “When I am lifted up from the earth, I will draw all things to myself.” Now he did not say this because he draws all men whatsoever, but because no one is saved unless he himself draws him. For he also says: “No one can come to me unless the Father who has sent me draws him.” He also says in another place: “Everything that the Father has given me will come to me.” Therefore, these are all the ones whom God wills to be saved and to come to the knowledge of the truth. Fathers of the Church, Vol. 126, Fulgentius of Ruspe and the Scythian Monks, Correspondence on Christology and Grace, trans. Bob Roy McGregor and Donald Fairbairn (Washington D.C.: The Catholic University of America Press, 2013), p. 101. See Epistola XVII in PL 65.
Latin text: Quos omnes homines Deus vult salvos fieri. Per omnes homines non semper totum genus humanum intelligitur.—61. Quocirca illos omnes quos Deus vult salvos fieri, sic intelligere debemus, ut nec aliquem putemus salvum fieri posse nisi voluntate Dei, nec existimemus voluntatem omnipotentis Dei, aut in aliquo non impleri, aut aliquatenus impediri. Omnes enim quos Deus vult salvos fieri, sine dubitatione salvantur, nec possunt salvari, nisi quos Deus vult salvos fieri, nec est quisquam quem Deus salvari velit qui (al. et) non salvetur: quia Deus noster omnia quaecunque voluit fecit. Ipsi omnes utique salvi fiunt, quos omnes vult salvos fieri: quia haec salus non illis ex humana voluntate nascitur, sed ex Dei bona voluntate praestatur. Verumtamen in his omnibus hominibus quos Deus vult salvos facere non totum omnino genus significatur hominum, sed omnium universitas salvandorum. Ideo autem omnes dicti sunt, quia ex omnibus hominibus omnes istos divina bonitas salvat, id est, ex omni gente, conditione, aetate, ex omni lingua, ex omni provincia. In his omnibus ille sermo nostri Redemptoris impletur, quo ait: Cum exaltatus fuero a terra, omnia traham ad meipsum. Quod non ideo dixit, quia omnes omnino trahit, sed quia nemo salvus fit, nisi quem ipse traxerit. Nam et alibi dicit: Nemo potest venire ad me, nisi Pater, qui misit me, traxerit eum. Item alibi: Omne quod dedit mihi Pater ad me veniet.Hi ergo sunt omnes quos vult Deus salvos fieri et ad agnitionem veritatis venire. Epistola XVII, Caput XXXI, §61, PL 65:489.
He goes on to state in the same letter…
Fulgentius, bishop of Ruspe (c. 467-532): These are all those on whom God has mercy because they are preceded by his mercy so that they may believe and be freely saved through faith. The fact that they believe does not take its beginning from the human will, but faith is given to the will itself in accordance with the free generosity of the merciful God. Blessed Paul recorded this distinction between different senses of the word “all” (a distinction that a faithful understanding must preserve completely) at one place in his letter so that even when he says “all men” without noting any exceptions, he might still indicate all men of a certain kind while excluding others. Fathers of the Church, Vol. 126, Fulgentius of Ruspe and the Scythian Monks, Correspondence on Christology and Grace, Fulgentius’s First Letter to the Scythian Monks, trans. Bob Roy McGregor and Donald Fairbairn (Washington D.C.: The Catholic University of America Press, 2013), p. 103.
Latin text: Hi sunt ergo omnes quorum Deus miseretur, quia misericordia ipsius praeveniuntur, ut credant et gratis salvi fiant per fidem. Eorum namque credulitas non ex humana voluntate sumit initium, sed ipsi voluntati fides gratuita Dei miserantis largitate donatur. Hanc omnium discretionem, quam fidelis debet intellectus omnino servare, beatus Paulus uno Epistolae suae loco sic posuit, ut omnes homines sine aliqua exceptione dicens, statim quosdam omnes homines exceptis aliis intimaret. Epistola XVII, Caput XXXI, §64, PL 65:490.
The citations above are simply two examples, but throughout this entire letter Fulgentius explains repeatedly to the Scythian Monks that the word “all” (with respect to those whom God desires to save) means all men without distinction, but not all men without exception.