'Mightier' in the Bible

My Father, who has given them to Me, is greater and mightier than all; and no one is able to snatch them out of the Father’s hand.

You heard Me tell you, ‘I am going away, and I am coming back to you.’ If you [really] loved Me, you would have rejoiced, because I am going [back] to the Father, for the Father is greater than I.