"As an apostle he spake divine truths, and was guided infallibly by the Spirit of God; he delivered truths without all conditions and exceptions...And you must know this, that God, as he used the apostles and excellent men to write his book, to write the word of God, to be his penmen, yet he hindered them not be men. As he hinders not godly men to be men, but at once they may be saints and men; so St Paul as a good man, desired to see them, with a reservation; but as an apostle, he spake in the certainty of divine truth...So the prophets and apostles, as men, they might be alterable without sin. For God will allow men to be men, and subject to mistakes...But as an apostle, his doctrine was without ifs and ands, without exception, as we say, 'if God permit,' &c. 'No,' saith he; 'as God is true, our word to you was not yea and nay.' So in the apostles, we must consider a difference of divine truths that they delivered as apostles, from those things that they purposed as men, and as holy men."
Sibbes, Richard Works of Richard Sibbes Volume 3: An Exposition of 2nd Corinthians Chapter One (Carlisle: The Banner of Truth Trust, 2001), 356.