It's appropriate, I think, that St. Pius X's feast should fall on the Thirteenth Sunday this year, considering the steps he took to prevent heresy from infecting the Church, and today's Gospel speaks of the ten lepers, leprosy being a type of heresy.

From the Holy Gospel according to Luke
At that time : It came to pass, as Jesus went to Jerusalem, that he passed through the midst of Samaria and Galilee.  And as he entered into a certain village, there met him ten men that were lepers.  And so on, and that which followeth.

A Homily by St. Augustine the Bishop Lib. 2 quæst. Evang. cap. 40
The ten lepers lifted up their voices and said : Jesus, Master, have mercy on us.  And when he saw them, he said unto them : Go, shew yourselves unto the priests.  And it came to pass that, as they went, they were cleansed.  Question : Why did the Lord send them unto the priests, that, as they went, they might be cleansed?  Lepers were the only class among those upon whose bodies he worked mercy, whom we find that he sent unto the priests.  Thus it is written that he said to a leper whom he had cleansed : Go, and shew thyself to the priest, and offer for thy cleansing, according as Moses commanded, for a testimony unto them.  We ask then, of what was leprosy a type, whereof they that were ridded of the same were said, not to have been healed, but rather, to have been cleansed. Leprosy is a disease which doth first appear in the skin, but destroyeth not immediately the strength, nor the use of feeling and the limbs.  By lepers, therefore, we may not unreasonably suppose such to be figured as have not the knowledge of the true Faith, but do shew forth divers parti-coloured teachings of error.  They hide not their witlessness, but do use all such wit as they have to make it manifest, and proclaim it in high-sounding phrases.  There is no false doctrine but hath some truth mixed up with it.  A man's discourse then, with some truths in it unequally mingled with falsehoods, and all confounded in one mass, is like to the body of one that is stricken with leprosy, whereon all manner of foul colours do appear in this and that place along with the true colour of the skin. Such men as these are banished out of the walls of the Church, to the end that haply when they stand afar off they may lift up their voices and to cry to Christ for pardon, just as those ten men that were lepers, which stood afar off, outside the village, lifted up their voices and said : Jesus, Master, have mercy on us.  That they styled him Master, (by which title I know not if any others are said to have besought the Lord for bodily healing,) doth sufficiently shew (or so I think) that leprosy signifieth false doctrine, whereof the Good Master doth cleanse us.

And about St. Pius X, although, being Sunday, his Lessons are not read this year:
Pope Pius X, whose name previously was Joseph Sarto, was born in the village of Riese in the Venetian province, to humble parents remarkable for their godliness and piety.  He enrolled among the students in the seminary of Padua, where he exhibited such piety and learning that he was both an example to his fellow students and the admiration of his teachers.  Upon his ordination to the priesthood, he laboured for several years first as curate in the town of Tombolo, then as pastor at Salzano.  He applied himself to his duties with such a constant flow of charity and  such priestly zeal, and was so distinguished by the holiness of his life, that the Bishop of Treviso appointed him as a canon of the cathedral church and and made him the chancellor of the bishop's curia, as well as spiritual director of the diocesan seminary.  His performance in these duties was so outstanding and so highly impressed Leo XIII, that he made him bishop of the Church of Mantua. Lacking in nothing that maketh a good pastor, he laboured particularly to teach young men called to the priesthood, as well as fostering  the growth of devout associations and the beauty and dignity of divine worship.  He would ever affirm and promote the laws upon which Christian civilisation depend, and while leading himself a life of poverty, never missed the opportunity to alleviate the burden of poverty in others. Because of his great merits, he was made a cardinal and created Patriarch of Venice.  After the death of Pope Leo XIII, when the votes of the College of Cardinals began to increase in his favour, he tried in vain with supplications and tears to be relieved of so heavy a burden. Finally he ceded to their persuasions, saying I accept the cross.  Thus he accepted the crown of the supreme pontificate as a cross, offering himself to God, with a resigned but stedfast spirit. Placed upon the chair of Peter, he gave up nothing of his former way of life.  He shone especially in humility, simplicity and poverty, so that he was able to write in his last testament : I was born in poverty, I lived in poverty, and I wish to die in poverty.  His humility, however, nourished his soul with strength, when it concerned the glory of God, the liberty of Holy Church, and the salvation of souls.  A man of passionate temperament and of firm purpose, he ruled the Church firmly as it entered into the twentieth century, and adorned it with brilliant teachings.  He restored the sacred music to its pristine glory and dignity ; he established Rome as the principal centre for the study of the Holy Bible ; he ordered the reform of the Roman Curia with great wisdom ; he restored the laws concerning the faithful for the instruction of the catechism ; he introduced the custom of more frequent and even daily reception of the Holy Eucharist, as well as permitting its reception by children as soon as they reach the age of reason ; he zealously promoted the growth of Catholic action ; he provided for the sound education of clerics and increased the number of seminaries in their divers regions ; he encouraged every priest in the practice of the interior life ;  he brought the laws of the Church together into one body ; he condemned and suppressed those most pernicious errors known collectively as Modernism ; he suppressed the custom of civil veto at the election of a Supreme Pontiff.  Finally worn out with his labours and overcome with grief at the European war which had just begun, he went to his heavenly reward on the twentieth day of August in the year 1914.  Renowned throughout all the world for the fame of his holiness and miracles, Pope Pius XII, with the approbation of the whole world,  numbered him among the Saints.