Philoxenus of Mabbug

Abraham, who was called, went forth after God, and he was not a judge of the voice which came to him, and he was not held back by race and kinsfolk, nor by country and friends, nor by any of the many other human ties. Immediately he heard the voice and knew that it was of God, he despised everything and went forth to Him, and hearkened unto Him with simplicity. And he held Him to be certain and sure in his mind by faith, and by the natural simplicity which acteth not cunningly with evil things; and as a boy after his father did he run towards the voice of God, everything being despised in his eyes immediately he heard the word of God.

And there was in him also the knowledge and discretion of nature, but he shewed his discernment in that he found it right to hearken unto God, Who had called him, as a servant to his lord, and as a slave to his Creator. And also to that knowledge in which he was placed he did not give power to investigate and to enquire why and for what reason he had been called by God, "Go forth from thy country, and from thy kinsfolk, and come to the land which I will show thee." And God did not reveal to him what the country was, in order that his faith might be the more victorious, and his simplicity appear.