He was steady and hard-working, but a complaint was made against him to his employer that he arrived late to work because he attended early morning Mass each day. When charged with his offense, he did not deny it and explained to his employer: "Sir, it may be true that I am later at my work than some of the other laborers, but I do my utmost to make up for the few minutes snatched for prayer; I pray you compare my work with theirs, and if you find I have defrauded you in the least, gladly will I make amends by paying you out of my private store."
His employer said nothing, but remained suspicious, and, being determined to find out the truth, rose one morning at daybreak and concealed himself outside the church. In due course, Isidore appeared and entered the building, and afterwards, when the service was over, went to his work. Still following him, his employer saw him take the plough into a field, and was about to confront him when, in the pale, misty light of dawn, he saw, as he thought, a second plough drawn by white oxen moving up and down the furrows. Greatly astonished, he ran towards it, but even as he ran it disappeared and he saw only Isidore and his single-plow.
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