Some of the most beautiful verses in scripture are ruined by being consistently taken out of context, and this is one of them:  "For My thoughts are not your thoughts, nor are your ways My ways, says the Lord.  For as the heavens are higher than the earth, so are My ways higher than your ways, and My thoughts than your thoughts" (Isaiah 55:8-9). 

Well, I guess that says it all, right?  God's mind is up there, and ours is down here, and never the twain shall meet.  

But wait a minute.  To whom was God speaking?  Probably the same people He was speaking to in the verses above, where he says "Seek the Lord while He may be found; call upon Him while He is near.  Let the wicked forsake his way, and the unrighteous man his thoughts; Let him return to the Lord, and He will have mercy on him; and to our God, For He will abundantly pardon."  

So, specifically, the "wicked" and "unrighteous" are the ones whose thoughts are not God's thoughts.  In other words, God is saying, "I'm not like you because my thoughts are thoughts of justice and mercy and my ways are ways of peace and satisfaction."  If we are the wicked and unrighteous, this verse is speaking to us and telling us that God is totally other than us, but are we the wicked and unrighteous?  

It gets better.  Check out the verses after our famous little section of scripture.  "For as the rain comes down, and the snow from heaven [heaven, where God's ways and thoughts are], and do not return there, but water the earth [earth, where the wicked and unrighteous are], and make it bring forth and bud, that it may give seed to the sower and bread to the eater, so shall my word be that goes forth from my mouth.  It shall not return to me void..." 

Rain and snow come from above, where God is, to earth, where we are, causing new life to grow up, back towards heaven, and this is accomplished by the word of His mouth, which is at the same time any of His promises, His promise of salvation, specifically, and His Son, the Word of God.  

God has taken great pains to send us righteousness in the form of Jesus, so that through His blood, His Spirit, and His eternal intercession we CAN know God's thoughts and ways.  That was the whole point of the gospel.  Jesus said as much in John 15:  "No longer do I call you servants, for a servant does not know what his master is doing, but I have called you friends, for all things that I heard from my Father I have made known to you."  

So, please.  When you read or quote Isaiah 55:8-9, use it as a picture of our previous condition and the condition of the whole world without Christ, but don't use it to say that we can't know our God.  The context tells us just the opposite.