"B'ahavah" means "with love." But what does love mean?
We like to assert (inaccurately) that the Inuit, the Eskimos, have multiple words for snow to indicate subtle differences in quality. Judaism, likewise, has a raft of words for sin. And the Greeks have numerous words for love, which found their way into Christian culture.
One Greek term is "philia," the kind of love that exists between two siblings. Philadelphia quite literally means "the city of brotherly love." Another word is "agape," the kind of love ascribed to God for humanity and vice versa. It is a spiritual kind of attachment, a chaste yearning. Then there is everyone's favorite, "eros," at the root of the sexual, sensual kind of longing that typifies romantic love between two people.
All of those terms describe familiar variations on emotion to us, but from the Jewish point of view they are beside the point. Love, in Hebrew (and Jewish tradition) is not primarily a kind of emotion, but a description of commitment.
Rabbi Lawrence Kushner describes love as the willingness to put another person's needs ahead of one's own interests. He tells a sweetly hilarious story of how, late one night, his pregnant wife expressed a craving for a particular candy bar, and how he wound up driving, in his pajamas, ending up in a hotel lobby doing battle with a vending machine trying to fulfill her desire. At that moment, his own needs - his ego - did not matter. All that mattered was fulfilling the needs of the one he loved.
When we affirm that God "brings a redeemer to [our ancestors'] children's children with love," we make a claim that God puts our need for redemption even above God's own interests. The promise of that rescue from the shackles of historical experience - the canvas on which God becomes known - is an indication that God's commitment to us is complete and absolute.
And the implication is, when we recite those words, that such love should be reciprocated. Our redemption will be effected when we put God's needs ahead of our own - with love.