AGESIMA (sorry, that's very adolescent). In this Pauline year, what a pity that Sexagesima is no longer observed. Statio ad S Paulum, say the old Missals. Septua' had the Statio at S Lawrence; Quinqua' will be at S Peter. S Gregory fixed these three Sundays at a time of great stress. Lombards were running riot and hauling away columns of chained prisoners to be sold into slavery. Monte Cassino had been attacked a a lot of its monks had taken refuge in Rome in the Mone of S Andrew on the Caelian Hill. S Gregory saw the three great basilicas on the outskirts of the City dedicated to the three great Patrons of Rome as spiritual fortresses defending the City. So, on these three Sundays, the congrgations had a long and penitential traipse outwards for their Sunday Mass.
So, if you have a proper Missal, look at these three sets of propers. You will see that Sexa' is very Pauline, with the reference in the collect to the Teacher of the Gentes, the Epistle about the apostolic exertions of S Paul, and the Gospel so suitable to those exertions. Look at the chants and discern their relevance to the troubles of the times.
Good news. Many of those dragged away into slavery took with them and disseminated their Christian Faith. And a gang of monks from S Andrew's were sent to evangelise the non angelos sed Anglos. Silver linings.