plus she said seal your army and focus on getting stronger your self..... now he has numen and light and dark spells, quite a bit more powerful so I think the god of light and God of darkness has a partnership
remember when he got the powers he saw the three of them standing together
now that i think about it more i think she did it to fool the outsiders, she is a schemer. if she truly wanted to kill Gabriel, she would had descended and kill him before he had a chance to regain power. Dont know why she did not tell him her plan.