Isa 48:18  Oh that you had paid attention to my commandments! Then your peace would have been like a river, and your righteousness like the waves of the sea; 
Isa 48:19  your offspring would have been like the sand, and your descendants like its grains; their name would never be cut off or destroyed from before me.” 

In Isaiah 48, God laments that Israel has not responded to Him. In verse 12, God calls on Israel to listen. In verse 14, God reminds Israel of the things He has done and said. In verse 17, God is said to “teach to profit”. God’s purpose in teaching is to make Israel better. Then verses 18 and 19 contain a lament. Although God has done and said all these things to benefit Israel, Israel has rejected Him.

The emotional pain drips from every word. The regrets, the lament, the failed possibilities are all at the forefront of God’s mind. God has been hurt by Israel due to their unbelief.