The strength of such a union is literally the strength of its weakest link.

Jenny loved both Isabel and Theophil, and both Isabel and Theophil loved Jenny; and in the love of the two girls, there was an element of affection that was more impassioned than friendship.

Jenny indeed loved Isabel so much that it might well have proved that her love, with nothing but gladness, could have added its volume to Theophil's, and the three loves, meeting in one river of love, flowed on together to the eternal sea.
But the tragic risk! The alternative was--heart-break, death.

They had vowed to save Jenny from the lightning.

Perhaps it would not destroy, but only transfigure, after all,--yet the test was lightning; and for whom that we love dare we venture such an ordeal, though it were to win them Paradise?
No! Jenny must never know.