As a believer in Jesus Christ, according to the New Testament, you have authority to pray and receive. Christ is the Mediator of the New Testament. He teaches you how to pray according to New Testament promises. The model prayer for every believer is the Lord's prayer.
Through faith in Jesus Christ, you have authority to ask God to do certain things in your life. You can ask God your Father to give you daily bread, forgive your sins as you forgive others, to lead you not into temptation, and deliver you from evil. Those are promises from the Lord's prayer. Jesus teaches you to pray those requests. You receive according to the New Testament of our Lord and Savior Jesus Christ.
The prayer God answers is based on the word of promise in the New Testament. God has declared His will for you. Ask and receive. Offer your request in the name of Jesus, the Mediator of the New Testament. He has all authority in heaven and in earth. Your authority as a believer is in the name of Jesus.
Authority in prayer is based upon the sure promises of the New Testament, and your confidence in the authority of Jesus Christ. Your faith simply takes the truth of God's word, and the authority in Jesus name, asking your Father in heaven to do what He has promised. You ask and receive to the glory of God.
"Jesus came and told his disciples,
'I have been given complete authority
in heaven and on earth."
Matthew 28:18, NLT