I AM...

After these things the word of the LORD came to Abram in a vision: “Fear not, Abram, I AM your shield; your reward shall be very great.”  Genesis 15:1 ESV
God said, "I AM".  Here, God tells Abram (known as Abraham later, when God renames him) that he will be rewarded for serving God faithfully, that the Messiah will come thru Abram's lineage.


57 So the Jews said to him, “You are not yet fifty years old, and have you seen Abraham?” 58 Jesus said to them, “Truly, truly, I say to you, before Abraham was, I AM.”  John 8:57-58 ESV
What was Jesus claiming here?  It's pretty big, this is why the religious folks killed Him.


61 But he remained silent and made no answer. Again the high priest asked him, “Are you the Christ, the Son of the Blessed?”  62 And Jesus said, “I AM, and you will see the Son of Man seated at the right hand of Power, and coming with the clouds of heaven.” 63 And the high priest tore his garments and said, “What further witnesses do we need? 64 You have heard his blasphemy. What is your decision?” And they all condemned him as deserving death.  
Mark 14:61-64 ESV
He remained silent on all accusations, until they asked him if he was the Messiah.  His response? 
"I AM".


I AM the Alpha and the Omega, the first and the last, the beginning and the end.”  Revelation 22:13 ESV
Jesus was crucified, on a legal basis in those times, because he claimed to be God.  These two single words got him murdered, "I AM".