The shock changed his whole tone. He could not bear to continue his journey, but turned back to Plymouth, determined to prove to himself what was indeed truth; and, while deeply studying the evidences of Christianity, he supported himself by keeping a school and writing educational books on grammar and arithmetic. His mind was soon thoroughly made up, as, indeed, his aberrations had been only on the surface, and he became very anxious to enter the Theological College at Andover, Massachusetts. This belonged to the most earnest of the Congregationalists, and evidence of personal conversion and piety was required from the candidates; but, in his case, the professors were satisfied, and he entered on his course of study, which included Hebrew. In the last year of his studies there he fell in with Claudius Buchanan's "Star in the East," and the perusal directed his whole soul to the desire of missionary labour. His mind was harassed night and day with the thought of longing to do something for the enlightenment of the millions in Asia; and, meeting with Symes' "Burmese Empire," his thoughts turned especially in that direction. It was a quiet steady purpose, though he was slow of communicating it; until, one evening at home, his father began throwing out hopes and hints of some great preferment, and his mother and sister smiled complacently, as if they were in the secret. Adoniram begged for an explanation, since it was possible their plans might not coincide, to which his father replied there was no fear, and told him that the minister of the biggest church in Boston wished for him as a colleague. "So near home," said the delighted mother. He could not bear to answer her, but, when his sister chimed in, he turned to her, saying, "No, sister, I shall never live in Boston; I have much farther to go;" and then, steadily and calmly, but fervidly, he set forth the call that he felt to be upon him. How different a communication from that which he had made two years before! No doubt his family so felt it, for, though his mother and sister shed many tears, neither they nor his father offered a word of opposition.