The Roman Catholic Church, according to the General Roman Calendar, celebrates the following in Monday, 2018-05-14:
Acts 1:15-17, 20-26
15In those days Peter stood up among the brethren (the company of persons was in all about a hundred and twenty), and said, 16"Brethren, the scripture had to be fulfilled, which the Holy Spirit spoke beforehand by the mouth of David, concerning Judas who was guide to those who arrested Jesus. 17For he was numbered among us, and was allotted his share in this ministry. 20For it is written in the book of Psalms, `Let his habitation become desolate, and let there be no one to live in it';and `His office let another take.' 21So one of the men who have accompanied us during all the time that the Lord Jesus went in and out among us, 22beginning from the baptism of John until the day when he was taken up from us -- one of these men must become with us a witness to his resurrection." 23And they put forward two, Joseph called Barsab'bas, who was surnamed Justus, and Matthi'as. 24And they prayed and said, "Lord, who knowest the hearts of all men, show which one of these two thou hast chosen 25to take the place in this ministry and apostleship from which Judas turned aside, to go to his own place." 26And they cast lots for them, and the lot fell on Matthi'as;and he was enrolled with the eleven apostles.
1Praise the LORD! Praise, O servants of the LORD, praise the name of the LORD! 2Blessed be the name of the LORD from this time forth and for evermore! 3From the rising of the sun to its setting the name of the LORD is to be praised! 4The LORD is high above all nations, and his glory above the heavens! 5Who is like the LORD our God, who is seated on high, 6who looks far down upon the heavens and the earth? 7He raises the poor from the dust, and lifts the needy from the ash heap, 8to make them sit with princes, with the princes of his people.
9As the Father has loved me, so have I loved you;abide in my love. 10If you keep my commandments, you will abide in my love, just as I have kept my Father's commandments and abide in his love. 11These things I have spoken to you, that my joy may be in you, and that your joy may be full. 12"This is my commandment, that you love one another as I have loved you. 13Greater love has no man than this, that a man lay down his life for his friends. 14You are my friends if you do what I command you. 15No longer do I call you servants, for the servant does not know what his master is doing;but I have called you friends, for all that I have heard from my Father I have made known to you. 16You did not choose me, but I chose you and appointed you that you should go and bear fruit and that your fruit should abide;so that whatever you ask the Father in my name, he may give it to you. 17This I command you, to love one another.
Psalms 68:2-3ab, 4-5acd, 6-7ab
R. Alleluia, alleluia.
If then you were raised with Christ,
seek what is above,
where Christ is seated at the right hand of the God.
R. Alleluia, alleluia.