Just think how much cooler the Olympics would be...
The text above it is on the left, the rubric (instructions) for the [c=#BF0000]Monday in the 3rd Week of Lent[/c], and on the right, part of the Old Testament lesson for that Mass - IV Kings (what we now call II Kings) 5:1-15) - specifically the words "[i][...Naaman's wife's maid waited upon][/i] Naaman's wife and said to her [i][mistress...][/i]".
Quite what this has to do with the joust, however, I've no idea. Maybe the point is to keep priests interested during masses...
Anyway it's fun, and it's from a 1492 Missal; 'Latin 16827' f.58v, in the Bibliothèque National de France) [https://gallica.bnf.fr/ark:/12148/btv1b60012792/f162.item.r=Latin%2016827]
