A proper attribute of God is mercy. It is not difficult for God to practice mercy, on the other hand, we by ourselves cannot feel mercy unless the Lord puts such a thing in our hearts. On the other hand, there are those who lose patience very easily, but our God is not like that, He is longsuffering and abounding in goodness.
But there is something important to understand, not only mercy is an attribute of God, but also anger, but not humanly like us, but in the sense that although God is longsuffering, He also punishes whe it is required. God is all love, but He also shows His wrath on the sons of wickedness. The Bible says:
The Lord is slow to anger, and great in power, and will not at all acquit the wicked: the Lord hath his way in the whirlwind and in the storm, and the clouds are the dust of his feet.
Nahum 1:3 (KJV)