user85944: are all nodes validate each transaction added in a new block?
Because what if someone said I have completed block and added invalid transaction? and if others node just accepts a block without validating a transaction.

user63872: 
are all nodes validate each transaction added in a new block?

Yes, each full node checks each transaction and block to make sure they are valid according to the network rules. 

85944: <p>are all nodes validate each transaction added in a new block?</p>

<p>Because what if someone said I have completed block and added invalid transaction? and if others node just accepts a block without validating a transaction.</p>
 63872: <blockquote>
  <p>are all nodes validate each transaction added in a new block?</p>
</blockquote>

<p>Yes, each full node checks each transaction and block to make sure they are valid according to the network rules. </p>
