1 Timothy 6:12

Fight the good fight of faith (in the conflict of evil); take hold of the eternal life to which you were called, and (for which) you made the good confession (of faith) in the presence of many witnesses.  

We must fight for faith, diligently practice confession, and study the Word. The mind doesn’t stay renewed and is easily distracted. Faith is our confession, and it must be spoken so our ears hear our words of faith, renewing the mind and building up our spirits.