With folded arms. This poor right hand of mine
Is left to tyrannize upon my breast,
Who, when my heart, all mad with misery,
Beats in this hollow prison of my flesh,
Then thus I thump it down.

He wants to stop the love he has for Lavinia because it’s mentally and emotionally hurting him

Thou map of woe, that thus dost talk in signs!
When thy poor heart beats with outrageous beating,
Thou canst not strike it thus to make it still.
Wound it with sighing, girl, kill it with groans;
Or get some little knife between thy teeth,
And just against thy heart make thou a hole,
That all the tears that thy poor eyes let fall
May run into that sink, and soaking in,
Drown the lamenting fool in sea-salt tears.

Titus expressing his pain to Lavinia