We are not to let the mind wander. We are to lift our minds in clear understanding and complete trust to our heavenly Father. If there is some place where life has become difficult, where things have gone wrong, where some uncleanness has possessed us, where some hostility or hate has entered our hearts, or some sin that needs forgiveness, we are to face it with God. God moves into the picture with forgiveness, with new hope in place of despair, with love instead of fear, with divine strength instead of weakness. A clear knowledge of what we say and what is taking place is needed.
Prayer is a very real and practical thing.
Before all the disorders of mind and heart that assail us, the temptations that make life difficult, prayer must be real and genuine, intelligent and understandable. We need the clearest minds possible when facing our personal problems. If there is a rift between us and God, we need to understand why. If we need forgiveness for a specific sin and all sins are specific we can have that from God. If we lack wisdom in some particular situation, then we ask God and we have that.