First reading 2 Timothy 3:10-17

Anyone who tries to live in devotion to Christ will be attacked

You know what I have taught, how I have lived, what I have aimed at; you know my faith, my patience and my love; my constancy and the persecutions and hardships that came to me in places like Antioch, Iconium and Lystra – all the persecutions I have endured; and the Lord has rescued me from every one of them. You are well aware, then, that anybody who tries to live in devotion to Christ is certain to be attacked; while these wicked impostors will go from bad to worse, deceiving others and deceived themselves.
  You must keep to what you have been taught and know to be true; remember who your teachers were, and how, ever since you were a child, you have known the holy scriptures – from these you can learn the wisdom that leads to salvation through faith in Christ Jesus. All scripture is inspired by God and can profitably be used for teaching, for refuting error, for guiding people’s lives and teaching them to be holy. This is how the man who is dedicated to God becomes fully equipped and ready for any good work.

Responsorial Psalm 118(119):157,160-161,165-166,168

The lovers of your law have great peace.
Though my foes and oppressors are countless
  I have not swerved from your will.
Your word is founded on truth,
  your decrees are eternal.
Though princes oppress me without cause
  I stand in awe of your word.
The lovers of your law have great peace;
  they never stumble.
I await your saving help, O Lord,
  I fulfil your commands.
I obey your precepts and your will;
  all that I do is before you.

Gospel Mark 12:35-37

‘David himself calls him Lord’
At that time while teaching in the Temple, Jesus said, ‘How can the scribes maintain that the Christ is the son of David? David himself, moved by the Holy Spirit, said:
The Lord said to my Lord:
Sit at my right hand
and I will put your enemies
under your feet.
David himself calls him Lord, in what way then can he be his son?’ And the great majority of the people heard this with delight.