Isaiah 30:18

"Therefore the LORD longs to be gracious to you, And therefore He waits on high to have compassion on you.  For the LORD is a God of justice; How blessed are all those who long for Him."

Three truths relating to our Lord's longing present themselves here:

I.  He is characterized as wanting and waiting to be graciously compassionate toward His own.

II. It is right that He would long for His children so deeply.

III. Blessing is promised to those of His children who have His same yearning.

I.  What a wonderfully-needed word for a weary soul!  How good of our loving Lord to reveal His heart's yearning for His own.  So similar is this to David's statements in Psalm 103: "The LORD is compassionate and gracious, Slow to anger and abounding in lovingkindness.  Just as a father has compassion on his children, So the LORD has compassion on those who fear Him.  For He Himself knows our frame;  He is mindful that we are but dust," (vv. 8, 13, 14).
Lessons which come to mind:
     a.  I cannot disappoint my Father, for He knows me completely, knows that I am but dust.  Nothing I do can ever catch Him by surprise, nor find Him making false assumptions about me.  He has no unrealistic expectations which cannot be met.
     b.  He is never indifferent to me.  The world about me often mocks the thought that God (if there IS one) would care one way or the other about this world, much less individual needs of the billions here.  Yet the living God is as great in His minuteness as He is in His magnitude, and, as Paul reminded the Roman believers: "He who did not spare His own Son, but delivered Him up for us all, how will He not also with Him freely give us all things?" (8:32)
     c.  My Father's eagerness to shower me with grace and compassion  encourages me to pray!  "Oh, Father!  Heighten my sensitivity to the many ways You show grace and compassion to Your undeserving child.  Call me and cause me to praise You, as You are worthy!"

II.  The uprightness of the LORD proclaimed by Isaiah echoes Moses's lyrics as recorded in Deuteronomy 32:  "For I proclaim the name of the LORD;  Ascribe greatness to our God!  The Rock!  His work is perfect, For all His ways are just;  A God of faithfulness and without injustice,  Righteous and upright is He," (vv. 3, 4).  
One of Satan's most potent and pervasive tactics to deceive mankind is to question God's character.  At the very outset of interacting with humanity, he asked Eve, "Has God said...?"  From then to now his character of skepticism has not changed, and his spirit of rebellion is at the heart of all doubting God's uprightness, justice, and goodness.  We lapse into this same attitude when we complain, contrary to God's command through Paul:  "Do all things without grumbling or disputing," (Philippians 2:14).  "Disputing" refers to questioning God, negatively... to criticize Him, either verbally or in our hearts.  Such a stance steals our joy, grieves and quenches the blessed Holy Spirit, and breaks our fellowship with the Father.  The antidote for such a poison?  Unconditional thanksgiving (Ephesians 5:20).

III.  "How blessed are all those who long for Him."  This is both an observation and a promise.  The most satisfied, fulfilled, and completed people on earth are those who long for the living God.  This longing is at the very heart of why we were created.  As the Westminster Shorter Catechism asks, "What is the chief end of man?"  Answer:  "Man's chief end is to glorify God, and to enjoy him for ever."  Enjoying God, responding in eagerness to His eagerness, is possible only through the Lord Jesus Christ.
Being dead in trespasses and sins, (Ephesians 2:1), the natural man is without saving faith, incapable of pleasing God (Hebrews 11:6), considering the things of the Spirit foolishness (I Corinthians 2:14).  Thus, it is understandable that such a one would avoid God's presence as much as possible.  
What does NOT make sense is the child of God, bought by the blood of the sinless Son of God, who experiences little eagerness to fellowship with his/her Father.  The only explanation is sin.  Sin it was, that caused Adam and Eve to try to cover themselves and hide from God's presence... and it has the same effect today.  Oh that we would continually refuse and forsake all that would hinder the fellowship our Father desires to enjoy with us!