Psalm 60

A Michtam of David. For teaching. When he fought against Mesopotamia and Syria of Zobah, and Joab returned and killed twelve thousand Edomites in the Valley of Salt.

...Moab is My washpot;
Over Edom I will cast My shoe;
Philistia, shout in triumph because of Me." v.8

Read chapter 60
This psalm is specifically for teaching.  Not a teaching of what to do or what not to do, but a teaching from a battle David fought in where there was loss and great victory.  How true it is that we can learn from battles in our life that despite just being in a battle and maybe facing loss we can still have victory.  
Because of the victory, the victor now boasts in the conquered territory that is his lot and goes in to describing each region and it's service and position to the Lord.  They're some interesting descriptions that I can relate to in my life.  Moab as His washpot is A mere pot to hold the dirty water after feet have been washed in it. Moab had defiled Israel, because of the counsel of Balaam.  "She now shall be a washpot for those whom she sought to pollute. The wicked as we see in them the evil, the fruit, and the punishment of sin, shall help on the purification of the saints. This is contrary to their will, and to the nature of things, but faith finds honey in the lion, and a washpot in filthy Moab. David treats his foes as but insignificant and inconsiderable; a whole nation he counts but as a footbath for his kingdom" (Surgeon). 
Edom gets a shoe cast on them.  Strange but perhaps it's like nowadays when men through their glove as a challenge to dare to dispute. "As a man when bathing throws his shoes on one side, so would he obtain his dominion over haughty Esau's descendants as easily as a man casts a shoe.  He did not need draw a sword to smite his now crippled and utterly despondent adversary, for if he dared revolt he would only need to throw his slipper at him, and he would tremble. Easily are we victors when Omnipotence leads the way" (Spurgeon).
How can you take such a place in your life of a dirty washout or show rack that it may honor and serve the Lord?