First Reading: Genesis 17: 1, 9-10, 15-22
1 And after he began to be ninety and nine years old, the Lord appeared to him: and said unto him: I am the Almighty God: walk before me, and be perfect.
9 Again God said to Abraham: And thou therefore shalt keep my covenant, and thy seed after thee in their generations.
10 This is my covenant which you shall observe, between me and you, and thy seed after thee: All the male kind of you shall be circumcised:
15 God said also to Abraham: Sarai thy wife thou shalt not call Sarai, but Sara.
16 And I will bless her, and of her I will give thee a son, whom I will bless, and he shall become nations, and kings of people shall spring from him.
17 Abraham fell upon his face, and laughed, saying in his heart: Shall a son, thinkest thou, be born to him that is a hundred years old? and shall Sara that is ninety years old bring forth?
18 And he said to God: O that Ismael may live before thee.
19 And God said to Abraham: Sara thy wife shall bear thee a son, and thou shalt call his name Isaac, and I will establish my covenant with him for a perpetual covenant, and with his seed after him.
20 And as for Ismael I have also heard thee. Behold, I will bless him, and increase, and multiply him exceedingly: he shall beget twelve chiefs, and I will make him a great nation.
21 But my covenant I will establish with Isaac, whom Sara shall bring forth to thee at this time in the next year.
22 And when he had left off speaking with him, God went up from Abraham.
Responsorial Psalm: Psalms 128: 1-2, 3, 4-5
1 Blessed are all they that fear the Lord: that walk in his ways.
2 For thou shalt eat the labours of thy hands: blessed art thou, and it shall be well with thee.
3 Thy wife as a fruitful vine, on the sides of thy house.
4 Behold, thus shall the man be blessed that feareth the Lord.
5 May the Lord bless thee out of Sion: and mayest thou see the good things of Jerusalem all the days of thy life.
Gospel: Matthew 8: 1-4
1 And when he was come down from the mountain, great multitudes followed him:
2 And behold a leper came and adored him, saying: Lord, if thou wilt, thou canst make me clean.
3 And Jesus stretching forth his hand, touched him, saying: I will, be thou made clean. And forthwith his leprosy was cleansed.
4 And Jesus saith to him: See thou tell no man: but go, shew thyself to the priest, and offer the gift which Moses commanded for a testimony unto them.