Al Green was the first great soul singer of the '70s and arguably the last great Southern soul singer. With his seductive singles for Hi Records in the early '70s, Green bridged the gap between deep soul and smooth Philadelphia soul. He incorporated elements of gospel, interjecting his performances with wild moans and wails, but his records were stylish, boasting immaculate productions that rolled along with a tight beat, sexy backing vocals, and lush strings. The distinctive Hi Records sound that the vocalist and producer Willie Mitchell developed made Al Green the most popular and influential soul singer of the early '70s, influencing not only his contemporaries, but also veterans like Marvin Gaye. Green was at the peak of his popularity when he suddenly decided to join the ministry in the mid-'70s. At first, he continued to record secular material, but by the '80s, he was concentrating solely on gospel. During the late '80s and '90s, he occasionally returned to R&B, but he remained primarily a religious performer for the rest of his career. Nevertheless, Green's classic early- '70s recordings retained their power and influence throughout the decades, setting the standard for smooth soul.