Lewis was elected to the Door of Virtue Lodge in January 1797 and had climbed the ranks to Past Master Mason within three months. By 1799 he had attained status of Royal Arch Mason in Widow’s Son Lodge at Milton, Virginia. Shortly thereafter Lewis had been chosen by Jefferson to be his private secretary. In September of 1808, after being named governor of Louisiana Territory, Lewis helped establish the first Masonic lodge in St. Louis and was named Master of St. Louis Lodge, Number 111. Below is his Masonic Apron:
