3 Nephi 7:16

therefore, being grieved for the hardness of their hearts, and the blindness of their minds, went forth among them in that same year, and began to testify boldly, repentance and remission of sins through faith on the Lord Jesus Christ.

He was sad because their hearts were hard and their minds were blind. So in that same year, he went out among them. He began to teach boldly about repentance. He taught them that their sins could be forgiven through faith in the Lord Jesus Christ.

His heart ached for their stubbornness and spiritual blindness. So that same year, he went out among them and began boldly preaching repentance and forgiveness of sins through faith in the Lord Jesus Christ.