First Reading: Isaiah 7:10-14
10 Again the LORD spoke to Ahaz:
11 Ask for a sign from the LORD, your God; let it be deep as the nether world, or high as the sky!
12 But Ahaz answered, “I will not ask! I will not tempt the LORD!”
13 Then he said: Listen, O house of David! Is it not enough for you to weary men, must you also weary my God?
14 Therefore the Lord himself will give you this sign: the virgin shall be with child, and bear a son, and shall name him Immanuel.
Psalm: Psalm 24:1-6
1 A psalm of David. The earth is the LORD’S and all it holds, the world and those who live there.
2 For God founded it on the seas, established it over the rivers.
3 Who may go up the mountain of the LORD? Who can stand in his holy place?
4 “The clean of hand and pure of heart, who are not devoted to idols, who have not sworn falsely.
5 They will receive blessings from the LORD, and justice from their saving God.
6 Such are the people that love the LORD, that seek the face of the God of Jacob.” Selah
Second reading: Romans 1:1-7
1 Paul, a slave of Christ Jesus, called to be an apostle and set apart for the gospel of God,
2 which he promised previously through his prophets in the holy scriptures,
3 the gospel about his Son, descended from David according to the flesh,
4 but established as Son of God in power according to the spirit of holiness through resurrection from the dead, Jesus Christ our Lord.
5 Through him we have received the grace of apostleship, to bring about the obedience of faith, for the sake of his name, among all the Gentiles,
6 among whom are you also, who are called to belong to Jesus Christ;
7 to all the beloved of God in Rome, called to be holy. Grace to you and peace from God our Father and the Lord Jesus Christ.
Gospel: Matthew 1:18-24
18 Now this is how the birth of Jesus Christ came about. When his mother Mary was betrothed to Joseph, but before they lived together, she was found with child through the holy Spirit.
19 Joseph her husband, since he was a righteous man, yet unwilling to expose her to shame, decided to divorce her quietly.
20 Such was his intention when, behold, the angel of the Lord appeared to him in a dream and said, “Joseph, son of David, do not be afraid to take Mary your wife into your home. For it is through the holy Spirit that this child has been conceived in her.
21 She will bear a son and you are to name him Jesus, because he will save his people from their sins.”
22 All this took place to fulfill what the Lord had said through the prophet:
23 “Behold, the virgin shall be with child and bear a son, and they shall name him Emmanuel,” which means “God is with us.”
24 When Joseph awoke, he did as the angel of the Lord had commanded him and took his wife into his home.