Using the text from John 15, we find that there are two criteria to meet prior to asking God for anything and it "SHALL" be done for you.  First, we must abide in our Lord Jesus Christ, the branch and be one with Him.  Second, His words or commandments must abide in us.  His words must be in our DNA and be part of us.  Only then can we confidently ask the Father for anything.  We then turn to Psalm 91 and find that this also has a criteria to meet prior to sheltering under the wing of the Most High.  It is TRUST.  We must cast all our cares on Him.  We must trust that the All Mighty is our fortress and refuge.  Depending on any other comfort, rescue, wisdom, or safety will not be beneficial to us.  It is in the complete trust in God that we see the protections from the evil one. 

Song "I've Become a New Man" by Mesquite Cafe.