Genesis 45:3
And Joseph said unto his brethren, I am Joseph; doth my father yet live? And his brethren could not answer him; for they were troubled at his presence. And Joseph said unto his brethren, I am Joseph; doth my father yet live? And his brethren could not answer him; for they were troubled at his presence.
Joseph makes himself known to his brothers only after he has tested and proved them and has seen in them signs and fruits of true repentance for their sins. Deeply overcome and deeply affected, he causes all others to leave so that he is left alone with his brothers, and he weeps aloud before he speaks to them. He then declares that he is Joseph and asks whether his father still lives.
His brothers cannot answer him, for they are speechless, astonished, startled, afraid, and troubled at his presence. They cannot believe that the ruler of Egypt standing before them is their brother Joseph, whom they had envied, whom they would have murdered, and whom they finally sold as a slave. All their ill treatment and cruelty toward him painfully comes before them as they remember what they did. Especially his dreams rise before them, dreams which they had despised and labored to prevent from coming true, yet by repeatedly making obeisance to him they themselves had helped fulfill and acted out, so that they stand before him condemned, ashamed, and amazed.
They are startled and afraid because they remember their cruelty and fear that he will take revenge on them. Their being troubled at his presence reflects the remorse and great distress of mind they have suffered ever since their cruelty toward him. They humbly confess the wrongs they committed against him and entreat his forgiveness. They also greatly rejoice to find that he is alive, and knowing that they are not guilty of his blood relieves their troubled minds.