You would think that one thing, would be one thing.  Not so, there are several, one things, that the Lord desires we understand, know, and need to do and even some we lack.

~  “But, beloved, be not ignorant of this one thing,”  (2 Peter 3:8)
Here Peter is giving us a Spiritual Truth:  “Gods ways are not our ways”, His Timeline, Mercy and Grace, His Love is beyond our understanding. 
Deuteronomy 29:29a
“The secret things belong unto the Lord our God:”
We need to concern ourselves with the truths the Lord has revealed to us and do His will.

~  “but this one thing I do”  (Philippians 3:13)
Paul is explaining how to attain the victory in our walk with God.
•  Forget:  The promises, plans, ambitions, desires, hopes and dreams of our Natural man.
•  Reach Forth:  Set your mind, desires, hopes, plans to Gods desire and plans for your life.
•  Press toward the prize:  Do the work and will of the Lord. 

If we do this one thing, He will keep our hearts and minds in perfect peace.

~  “one thing I know,”  (John 9:25)
John tells us the man was born blind and now he sees.  Is there anything we know, that is unshakable, impossible to question, that our hearts and minds know beyond a shadow of doubt?

~  “One thing thou lackest”  (Mark 10:21)
~  “Yet lackest thou one thing” (Luke 18:22)
This one thing is mentioned in two Gospels, and is a bit off putting.  “Sell what you have, and give to the poor.”  Now God is downright meddling.

The question is;  What are you willing to give up to follow the Lord?  Can you leave your creature comforts?  Will you give up your life, to gain it?

If you will, you will find eternal treasures.

~  “one thing is needful”  Luke 10:42
This is so important, to learn to sit at the feet of Jesus.  Trust, Rest and Rely on Him to Guide, Direct and Protect us in all that we do.

~  “even one thing befalleth them”
(Ecclesiastes 3:19)
Death comes to man and beast. Where will you spend Eternity?

~  “One thing have I desired ”  (Psalm 27:4)
This is where the rubber meets the road.  The Psalmist tells us his one desire, the “one thing” he seeks is to dwell in the house of the Lord, to know God. 

~  “not one thing hath failed”
~  “not one thing hath failed“ (Joshua 23:14)
Twice in one verse the Lord emphasized; “not
one thing hath failed of all the good things which the Lord your God spake concerning you; all are come to pass unto you, and not one thing hath failed thereof.”

The promises of God are yea and amen:

2 Corinthians 1:20
“For all the promises of God in him are yea, and in him Amen, unto the glory of God by us.”

2 Corinthians 7:1
“Having therefore these promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God.”

One Thing….  One Thing indeed:

Matthew 11:28-30
King James Version (KJV)
“Come unto me, all ye that labour and are heavy laden, and I will give you rest.  Take my yoke upon you, and learn of me; for I am meek and lowly in heart: and ye shall find rest unto your souls.  For my yoke is easy, and my burden is light.”

Lord, draw us close to You.  Amen