The aim of this article is to present a set of glosses to the Qurʾān written by the sixteenth-century Spanish convert Juan Gabriel and to analyze them in the context of apologetic argumentation. The glosses come from a translation commissioned by Egidio da Viterbo (1518). I present here the index of topics covered by the glosses and argue for their conciliatory character. I also select glosses that focus on the identity of Abraham and compare them with annotations that appear in other Latin translations of the Qurʾān. The conclusion of this study is that, although there was a tradition in Latin Europe of glossing the Qurʾān in particular places, for example in passages where biblical figures are mentioned, Juan Gabriel used this tradition to present Islam as compatible with Christianity rather than a heresy.