Message In An Acrostic Contest

A nickname for night soil, that's surely no lie Pair upwards to double, a straight multiply For music we're singing a simple duet Use binary coding for computers, no sweat We're even the first that's not at all odd With religious duality, Satan and God The turtle doves given by Christmas day love To walk without hopping, our legs total of Twin oxygen atoms in water or ice Line's second word - there's no need to say twice Entry for "message in an acrostic" contest Note: take first letter from second word in each line - and time is ticking 14th January 2017