Genesis 26:33

Abraham had called this well ‘Beer-sheba’. (See Genesis 21:31.) That means ‘the well of 7’. The number 7 was a sign of an agreement. (See the comment on Genesis 21:27-30.) Isaac calls it ‘Shibah’, which means ‘agreement’. ‘Shibah’ is almost the same word as ‘sheba’. Isaac might have said, ‘Abraham called this well “the well of 7”. I call it “the well of the agreement” because I have made an agreement with Abimelech. But my name for the well is the same as Abraham’s name for it.’