The strongest choice would be:
General Electric Silicone II
A less toxic alternative would be:
but it isn't as strong.
The fastest and also less toxic recommendation would be:
Whenever you are gluing glass you must consider
the visibility of the
adhesive. If the glass is translucent or transparent, you will want a glue that dries as
clear as possible.
Before gluing any glass bond be sure that the glass is clean, free of any
oil (even from your fingers) and dry.