Ali 'Imran 3:67

مَا كَانَ إِبْرَٰهِيمُ يَهُودِيًّا وَلَا نَصْرَانِيًّا وَلَـٰكِن كَانَ حَنِيفًا مُّسْلِمًا وَمَا كَانَ مِنَ ٱلْمُشْرِكِينَ

Mā kāna ib'rāhīmu yahūdiyyan walā naṣrāniyyan walākin kāna ḥanīfan mus'liman wamā kāna mina l-mush'rikīna

Abraham was neither a Jew nor a Christian, but he was one inclining toward truth, a Muslim [submitting to Allāh]. And he was not of the polytheists.