Responsorial Psalm: Psalm 39(40):7-11

Here I am, Lord! I come to do your will.

You do not ask for sacrifice and offerings,
  but an open ear.
You do not ask for holocaust and victim.
  Instead, here am I.

Here I am, Lord! I come to do your will.

In the scroll of the book it stands written
  that I should do your will.
My God, I delight in your law
  in the depth of my heart.

Here I am, Lord! I come to do your will.

Your justice I have proclaimed
  in the great assembly.
My lips I have not sealed;
  you know it, O Lord.

Here I am, Lord! I come to do your will.

I have not hidden your justice in my heart
  but declared your faithful help.
I have not hidden your love and your truth
  from the great assembly.

Here I am, Lord! I come to do your will.