1 Corinthians 3:13

Every man's work shall be made manifest
The doctrine he preaches shall be sooner or later made manifest to himself, and to his hearers; who shall see the inconsistency, irregularity, and deformity of such a building; at first so well laid, then piled up with such excellent materials, and at last covered in with such trifling or incoherent stuff:

for the day shall declare it;
meaning not the day of judgment, though that is often called the day, or that day, and will be attended with fire, and in it all secrets shall be made manifest; but the apostle intends a discovery that will be made of doctrines in this world, before that time comes: wherefore this day rather designs a day of tribulation; as of persecution, which tries men's principles, whether they are solid or not; and of error and heresy, when men are put upon a re-examination of their doctrines, whereby persons and truths that are approved are made manifest; or of some great calamity, such as the destruction of Jerusalem, whereby many wrong notions the Jews yet retained were discovered: but it is best of all to understand this day of the Gospel day, and of the progress of Gospel light, especially in some particular periods of it; as in the primitive times, at the reformation from popery, and the more remarkable Gospel daylight, which will be in the latter times, when the impertinence and inconsistency of many things which now obtain in the ministry will be seen; see ( Ephesians 5:13 ) .

Because it shall be revealed by fire:
not that day, but the man's work, or doctrine:

and the fire shall try every man's work of what sort it is;
by the fire is meant, not the general conflagration of the world, when that, and all that is therein, will be burnt up; much less the fire of purgatory, the "papists" dream of, for the punishment of evil actions; for the apostle is not speaking of the actions of men, good or bad, but of the doctrines of ministers; rather the fire of tribulation and affliction, which, as it is for the trial of the grace of faith, so of the doctrine of faith, whereby it becomes much more precious than of gold that perisheth; or of some fiery dispensation of God's vengeance, as on Jerusalem: though the word of God, which is as fire, seems to be intended; which in some certain times so blazes forth, and will more especially in the latter day, that by the light of it, both ministers and churches will be able to see clearly the bright shining lustre of the gold, silver, and precious stones; and with so much heat, as to burn up the wood, hay, and stubble; when the difference between these things will be most easily discerned.