First, she warns us that life is a warfare, as Job realised (Offertory). She warns us against the “deceits of the devil,” trying to destroy our riches of Divine Grace. She warns us also “against flesh and blood.” as explained in the Epistle, which also describes what the well-equipped Christian must wear for this war. But God will be “our refuge” (Gradual).
Consoling too are the words of Mardochai (Introit), confiding in God even when his beloved people faced destruction. Our second preparation consists in forgiveness of all injuries suffered during this life-struggle, even as we, relying on Divine Mercy, expect the forgiveness of all debts to the Divine Justice (Gospel).
The Prayer, Secret and Communion are in line with these sentiments of struggle against flesh and devil and of the exercise of charity toward our neighbour.
Although not commemorated in the Mass using the rubrics of the 1962 Missale Romanum, the 9th October marks the feast of one of the great Italian clergymen of the XVI Century, St. John Leonardi C., he helped found the Propaganda College in Rome whose goal was missionary work. In the same Mass SS Denis, Rusticus and Eleutherius Mm. are commemorated.
First Bishop of Paris, St. Denis was sent as a missionary to Paris by Pope Fabian in the middle of the III Century where he was beheaded with Rusticus, a priest, and the deacon, Eleutherius, near present day St. Denis. St. Denis is one of the Fourteen Holy Helpers invoked in cases of demonic possession.
Although not commemorated under the newer rubrics of the Mass, pray to the Saints for missionary success!