“This passage refers to either those teaching or listening to the Word of God. Paul wants men to uncover their heads in the public assembly. Let us discern whether they should follow this from general principal, or for a specific purpose. To be sure, Paul is not laying down everlasting and unchanging laws; instead he is giving instructions as to what is customary and honorable. Therefore this custom does not mandate that men must keep their heads completely bare during winter-time and frost, especially in cold regions or when the cold hurts the head. Naturally, people are free from certain external practices, but in such a way that the public custom is upheld. That which maintains public decency and is customary should not be defiantly disregarded.”
Annotations on the Evangelical History of our Lord Jesus Christ, p. 473. Zurich, 1529
Head Covering History 