יהוה the one and only true God, of Scripture, is immutable. He does not, and He cannot change else He would not to be God. Scripture is clear in this regard (See Numbers 23:19, Psalm 102:35-37, Malachi 3:6, Pslam 33:11, Pslam 138:8, Hebrews 6:17, Hebrews 13:18, James 1:17, etc.). This means that we can count on God fulfilling every promise found in Scripture. God’s immutability assures us that the Gospel of Jesus is faithful and true, that He died and rose from the dead as prophecied in Scripture to reconcile sinners to God and purchase salvation for all who would believe by God’s grace alone, through His gift of faith alone, in Christ alone, for God’s glory alone.
Allah on the other hand, although he claims in the Qur’an to be the same God of Scripture, doesn’t not bear the same divine attribute of immutability. Allah changes. The Islamic doctrine of Abrogation clearly denotes the mutability of Allah. Allah commanded Muhammed in Sura Al-Baqarah 2:191 to “Kill them wherever you come upon them and drive them out of the places from which they have driven you out. For persecution is far worse than killing. And do not fight them at the Sacred Mosque unless they attack you there. If they do so, then fight them—that is the reward of the disbelievers.” He commands Muhammed to kill all in battle. But then at the battle of Badar Muhammed and his people do not kill all their enemies and instead take captives to sell as slaves. Allah’s response is not justice for Muhammed’s outright disobedience but Allah changes His previous command to kill all enemies, and instead, in Sura Al-Anfal 8:67-69 states, “67. It is not for a prophet to take prisoners before he has subdued the land. You desire the materials of this world, but God desires the Hereafter. God is Strong and Wise.
68. Were it not for a predetermined decree from God, an awful punishment would have afflicted you for what you have taken.
69. So consume what you have gained, legitimate and wholesome; and remain conscious of God. God is Forgiving and Merciful.” Allah now says that Muhammed can only take captives once “the land is subdued” and then completely ignores Muhammed’s sin and disobedience telling him that what he has done is “legitimate and wholesome.” Allah responds to the sin of his people not with justice but excusing their sin in the name of his “mercy.” But if Allah is God as the Qur’an claims then he should necessarily be immutable, just, and merciful without sacrificing one for the other and certainly not changing his command and will in response to the sin of his people.
יהוה the One and Only God is not Allah and Allah cannot possibly be the same God of Scripture. יהוה is immutable, but Allah is mutable and therefore not God.