"For let not that man think that he shall receive any thing of the Lord.
"A double minded man is unstable in all his ways." (James 1: 7-8)
What makes a man double-minded?
I used to think that a double-minded man was a believer who was sinning, or a believer who did not believe everything about Jesus Christ.
I have since learned the importance of rightly dividing the Word of God (2 Timothy 2: 15)
How are we supposed to ask God for anything:
"But let him ask in faith, nothing wavering. For he that wavereth is like a wave of the sea driven with the wind and tossed." (James 1: 6)
In faith, we ask for God. Yet if we are under, trying to earn through our own efforts what God so freely gives, then He cannot help us:
"And the law is not of faith: but, The man that doeth them shall live in them." (Galatians 3: 120
A man who is under law is "double-minded" or "double-souled", because like the believer whom Paul describes in Romans 7, he wills what he cannot do, and he ends up doing what he cannot do, and in his struggle he is looking at Himself instead of trusting the Lord, who with Himself freely gives all things (Romans 8: 31-32)
As long as we are pressing ourselves to live out the Lord's life in our own efforts, we are not walking in the Spirit, and thus we frustrate the grace of God in our lives (Galatians 5: 4)
To walk by faith, we then receive His grace, and through His grace, we receive all things.
Therefore, be established in Christ's righteousness, knowing and believing that you are no longer under law., but under grace (Romans 6: 14)
Under grace, your faith works through Him, and thus in you there will he "nothing wavering."