Studies into homosexuality and Roman Catholic priests are difficult to quantify specific percentages of gay clergy. Roman Catholic priests who minister in Catholic dioceses make a promise to their bishop of celibacy at their ordination and as such agree to refrain from genital sexual activity with another person. In addition, the official position of the Catholic Church, while calling for the 'respect' of homosexuals, condemns as sinful any active homosexual lifestyle. Nevertheless several studies suggest that there are higher than average numbers of homosexual men (active and non-active) within the Catholic priesthood and higher orders.