God's gift to mankind
1. Something or someone that is considered a benefit to all of mankind. Artistic expression is truly God's gift to mankind. Jonathan has such an inflated ego, like he's God's gift to mankind or something.
2. Someone who is or is considered to be extremely attractive and/or irresistible to men. Walking down the red carpet in a stunning black dress, she looked like God's gift to mankind.
one small step for man, one giant leap for mankind
A phrase typically said in reference to a breakthrough or advancement of some kind. Astronaut Neil Armstrong famously said the phrase in 1969 when he became the first person to set foot on the moon. I think the self-driving car will be one small step for man, one giant leap for mankind. When we find a cure for this illness, it will be one small step for man, one giant leap for mankind.