'All men' means Gospel hearers in external communion — even the vicious — not only the faithful
Pareus was unnecessary: Le Blanc's own theses already prove Reformed common doctrine that each of the faithful can and ought be certain of grace without special revelation, and that such certainty is commonly called faith-certainty — so lack of it marks infirmity, not unbelief of the fundamentals.
The opponent's conjecture fails: 'all and each men' did not mean only the faithful.
Nor did Le Blanc mean Rome charges a duty on absolutely every human without exception; he meant all Gospel hearers in external church communion — even those who are wicked.
Latin
CXLIII. Sed nihil opus fuit viro docto hic citare Paraeum. Nam ipsae meae Theses, quas illi carpere libuit, integrae fere in eo insumuntur, ut probent secundum communem Reformatorum doctrinam, 1. Fideles singulos absque speciali revelatione, posse certo credere se esse in Dei gratia: 2. Fideles singulos, non tantum posse, sed etiam debere ea de re certo persuasos esse; & si de eo certi non sint, istud quendam defectum & quandam infirmitatem, in eorum fide arguere: 3. Denique Certitudinem illam communiter apud Reformatos certitudinem fidei vocari. Itaque vir Doctus in sua conjectura fallitur. Nam per omnes & singulos homines, non intellexi solummodo omnes & singulos fideles. Nec tamen mens mea fuit Reformatos accusari ab Ecclesiae Romanae Doctoribus, quod doceant omnes homines in universum, absque ulla exceptione, teneri certo credere se esse in Dei gratia. Verum per omnes & singulos homines intellexi omnes & singulos quibus annuntiatur Evangelium, & qui sunt in externa Ecclesiae communione; etiamsi alioqui flagitiose vivant & vitiis indulgeant.