Jamieson, Fausset and Brown on Genesis 45:3

3. I am Joseph--or, "terrified at his presence." The emotions that now rose in his breast as well as that of his brethren--and chased each other in rapid succession--were many and violent. He was agitated by sympathy and joy; they were astonished, confounded, terrified; and betrayed their terror, by shrinking as far as they could from his presence. So "troubled" were they, that he had to repeat his announcement of himself; and what kind, affectionate terms he did use. He spoke of their having sold him--not to wound their feelings, but to convince them of his identity; and then, to reassure their minds, he traced the agency of an overruling Providence, in his exile and present honor [Ge 35:5-7]. Not that he wished them to roll the responsibility of their crime on God; no, his only object was to encourage their confidence and induce them to trust in the plans he had formed for the future comfort of their father and themselves.