The psalmist acknowledges God as his shield or in other words God is his defence. God is also his glory as well as the lifter up of his head. These are the three things that the psalmist has found here of God.
A shield is a defensive weapon that a soldier uses in the battlefield to protect himself from the fiery darts or arrows or sword of the enemy soldier. When we are attacked by the enemy of our soul, do we have God with us as our shield and as our only present help in times of trouble? Do we run here and there in shame and defeat or do we ask God to protect us and to lift our heads up? What do we do during adversities? The psalmist had nowhere to go except God and he had no other defence other than God. He asks God to lift his head up from shame and defeat. He acknowledges God as his glory. When his enemies taunted him saying that he has no help from God, he confessed his confidence and courage in the Lord whom he served.
Do not get bogged down when things go haywire. Just arise from your shame and shake off the dust from your feet and shout aloud that God is your shield and the lifter up of your head. In the very place that you experienced defeat and shame, you will be led to victory and praise. May God bless you?