In order for old defeating thoughts to be invaded, conquered, and replaced by new, victorious ones, a process of reconstruction must transpire.
The best place I know to begin this process of mental cleansing is with the all-important discipline of memorizing Scripture. I realize it doesn’t sound very sophisticated or intellectual, but God’s Book is full of powerful ammunition! And dislodging negative and demoralizing thoughts requires aggressive action. I sometimes refer to it as a mental assault.
Charles Swindoll