Prayed during the Sacrament of Penance and Reconciliation, this prayer can also be prayed whenever we want to offer God our sorrow for failing to love him as we ought.

O my God,
I am heartily sorry for
having offended Thee,
and I detest all my sins,
because of thy just punishment;
but most of all because
they offend Thee, my God,
Who are all good and
deserving of all my love.
I firmly resolve,
with the help of Thy grace,
to confess my sins,
to do penance,
and to amend my life.

Amen.