You said, 'No, we will flee on horses.' Therefore you will flee! You said, 'We will ride off on swift horses.' Therefore your pursuers will be swift!
NIV
And you said, No! We will speed [our own course] on horses! Therefore you will speed [in flight from your enemies]! You said, We will ride upon swift steeds [doing our own way]! Therefore will they who pursue you be swift, [so swift that]AMP
But ye said, No; for we will flee upon horses; therefore shall ye flee: and, We will ride upon the swift; therefore shall they that pursue you be swift.
KJV