Mercy is one of the Lord's many attributes. In chapter 39 God has mercy on Ebed-melech and said "Because you trusted me,...I will rescue you and keep you safe". God has mercy on us, when we come to Him and put our trust in Him to save us.
God's name is great. In verse 26 of Chapter 44 God Himself says "I have sworn by my GREAT NAME". We are to call on His great name, worship His name, fear His name, and glorify His name.