BEING FILLED WITH THE KNOWLEDGE OF HIS WILL

"FOR THIS REASON WE ALSO, SINCE THE DAY WE HEARD IT, DO NOT CEASE TO PRAY FOR YOU, and to ASK that you may BE FILLED WITH THE KNOWLEDGE OF HIS WILL IN ALL WISDOM AND SPIRITUAL UNDERSTANDING."
Colossians 1:9 (NKJV)

Comment: Considering the content of the prayer prayed by Apostle Paul for the believers in Colosse, one would agree that it is a prayer that should be prayed by every believer daily.
The content: " . . . TO ASK THAT YOU MAY BE FILLED WITH THE KNOWLEDGE OF HIS WILL IN ALL WISDOM AND SPIRITUAL UNDERSTANDING" (Colossians 1:9).
a. Being filled with the knowledge of God's will starts with daily reading and studying of the written Word (Joshua 1:8; Psalm 1:2).
b. It does not end there, the practice of whatever you read and studied is of paramount importance also. In other words, you apply the Word daily to your life (James 1:22,25).
Through the application of the written Word in your day-to-day living, you get to know the will of God practically, not theoretically—but experientially. This is the major means or way through which a believer get to be filled with the knowledge of God's will.
The passage also says: " . . . IN ALL WISDOM AND SPIRITUAL UNDERSTANDING." It means the Word being practiced is translated or changed to the experiential knowledge or wisdom—It becomes pratical or firsthand experience.

Many so-called believers were able to aquire the head knowledge of the Bible, but they do not practice what they claimed to know.
It is through the practicing of the written Word that you get to have the knowledge of God's will; which is experiential knowledge or wisdom or first-hand experience of the written Word—your experience and engagement with the Word of God directly.
Through your daily living or walking with God, by the application of the written Word, your spiritual understanding is enhanced—increased or improved in value and quality. You have deeper understanding of the spiritual things.
God is Spirit and those who worship or walk with Him must do that in the spirit—through their recreated human spirit (John 4:24).
Since It is a spiritual walk with God, your understanding of spiritual things is bound to increase greatly, as you are consistent in your walk with Him—God.
There is no shortcut to this thing except you walk as it is being described or expatiated here.
If you consistently pray this Pauline prayers:
a. you would have quest to know the Bible the more,
b. and in a bid to do that, the desire to practice what you know would well up or spring up in you; being given to you by God through the Holy Spirit.
c. And with that desire given by God, you see yourself practicing the Word of God, the Bible.
d. Afterwards, you see yourself growing in the knowledge of God's will, and your spiritual understanding is being developed or increased at the same time.
In summation, knowledge of God's will—determination, choice, volition, purpose decree—is the practical things you learn or get to know about God in your daily walk with Him; through the application of the written Word of God—Bible.
Peace.