O God, be attentive unto helping me; O Lord, make haste to help me.
Let them be shamed and confounded that seek after my soul.
Let them be turned back and brought to shame that desire evils against me.
Let them be turned back straightway in shame that say unto me: Well done! Well done!
Let them be glad and rejoice in Thee all that seek after Thee, O God,
and let them that love Thy salvation say continually: The Lord be magnified.
But as for me, I am poor and needy; O God, come unto mine aid.
My helper and my deliverer art Thou, O Lord; make no long tarrying.
(Psalm 69, The Psalter according to the Seventy, Psalm 70:3 in Western Bibles)
What is meant by "Well done. Well done."?
I am interested in answers from authorised Eastern Orthodox sources.