The following text is extracted and adapted from Imam al Ghazali’s (r.a) al-Maqsad al-asna fi sharh asma Allah al-husna.
“Allah! there is no god but He! To Him belong the most Beautiful Names.” -Quran 20:8
Al-Sabur—the Patient—is the one who does not let haste move him to carry out an action before its time, but rather decides matters according to definite plan, and brings them about in delineated ways; not keeping them from their appointed time as a lazy person would do by procrastinating, nor bringing them forth before their time as a precipitate person would by hastening—but rather disposing each thing in its proper time, in the way in which it needs to be and according to what it requires. And all that without being subjected to a force opposing His will.
So far as man’s patience is concerned, it will require endurance, since the meaning of patience for him involves affirming religious or rational resolve in opposing the impulses of passion or anger. And if two opposing motives contend for him, and he repels the impulse leading to rashness and haste yet inclines to the one inducing him to delay, he will be called patient, since he caused the impulse to haste to be overcome.
In the case of God—may He be praised—inclination to haste is non-existent; so far as haste is concerned, He is farther from it than anyone in whom an inclination exists  yet is overcome, so He is the one most deserving of this name-rafter one has removed from consideration any conflict of inclinations or any need to overcome them by way of exertion.