whether all who believe in Christ will be saved

"...it is a very gross error of certain simple people, that think it to be enough to their salvation, if they believe in Christ, and that he died for their sins, although they believe not many other things; for example's sake, those which belong to Sacraments, Sacrifice of the Church, and other such like points of faith. For so should almost all sects of heretics be saved, for that all...do embrace Christ...and believe that he died for their sins. And so by this means shall be saved the Montanists and Novations...the Arians, Macedonians...Moneothelites, and such like pests of the Church. Wherefore then, hath the Church in all ages vehemently opposed herself against heresies? Wherefore doth the Apostle command us to avoid a heretical man after one or two reprehensions? Wherefore should we beware of their very speechs, as a certain infectious canker?"

"In vain then are all these things spoken and done, if salvation may be obtained together with heresy...let us imagine (saith St. Augstine) a man to be chaste, continent, not covetous, not a server of idols, liberal to the poor, no man's enemy, not contentious, patient, quiet...somber, frugal...but yet a heretic: let there be no doubt at all to any, but that such a one, for this only thing, in that he is a heretic, shall not possess the Kingdom of God."

"For as that man who offendeth in one commandment is made guilty of all, and looseth his whole justice, although he keep the rest of the commandments, because he contempteth the lawmaker himself who made the whole law...so he that denieth obstinately but one article of the faith, though he retain the rest, is made guilty of his whole Religion, and looseth all his Faith and Religion..."

from A Consultation what Faith and Religion is best to be Imbraced by Leonardus Lessius