“Let us therefore come boldly unto the throne of grace, that we may obtain mercy, and find grace to help in time of need.” Hebrews 4:16
To me boldness is a word that brings together three things: obedience, honesty, confidence.
Obedience is giving ear to; listening to; (where listening is an active verb that means to act on what you have heard).
Honesty is adherence to the facts.
Confidence is knowing what has been given to you. As in when someone confides in you.
Prayer to me is a conversation with God. And I believe that it is a conversation that He starts. Whenever I get the urge to pray I take that as Him gently tapping me on the shoulder saying, "I would like to spend some personal time with you." So prayer is a response to God speaking to us. Just as we can love Him because He first loved us... we can talk with Him (not just to) because He first talked with us.
Just as every conversation we have with other people is different because every person is different, I believe that our conversation with the Lord is going to demonstrate who we are and reflect where we are with Him.
So "boldness" in prayer, to me,