The Greek word used here “makrothumei” denotes “longanimity,” slowness to anger or passion; long-suffering, patient endurance, forbearance. It is opposed to haste; to passionate expressions and thoughts, and to irritability. It denotes the state of mind which can bear long when oppressed, provoked, calumniated, and when one seeks to injure us.”

“It can endure evil, injury, and provocation, without being filled with resentment, indignation, or revenge. It makes the mind firm, gives it power over the angry passions, and furnishes it with a persevering patience, that shall rather wait and wish for the reformation of a brother than fly out in resentment of his conduct. It will put up with many slights and neglects from the person it loves, and wait long to see the kindly effects of such patience on him.”

Those two quotes describe the kind of long-suffering God has for us. We hurt Him repeatedly with our actions, and He continues to wait for us to come to Him. He doesn't give up. He keeps sending people or circumstances our way to help us see God for the loving Father that He is and to encourage us to give our lives over to Him. He doesn't force Himself on us. He waits patiently, calling us to Him, showing us He loves us, hoping that we will give ourselves to Him so that He can create in us, the same kind of long-suffering love He displays toward us. We just have to ask.