Esias 30:16

16 but ye said, We will flee upon horses; therefore shall ye flee: and, We will be aided by swift riders; therefore shall they that pursue you be swift.

Esias 30:16 In-Context

14 And the fall thereof shall be as the breaking of an earthen vessel, small fragments of a pitcher, so that thou shouldest not find among them a sherd, with which thou mightest take up fire, and with which thou shouldest draw a little water.
15 Thus saith the Lord, the Holy Lord of Israel; When thou shalt turn and mourn, then thou shalt be saved; and thou shalt know where thou wast, when thou didst trust in vanities: your strength became vain, yet ye would not hearken:
16 but ye said, We will flee upon horses; therefore shall ye flee: and, We will be aided by swift riders; therefore shall they that pursue you be swift.
17 A thousand shall flee because of the voice of one, and many shall flee on account of the voice of five; until ye be left as a signal-post upon a mountain, and as one bearing an ensign upon a hill.
18 And the Lord will again wait, that he may pity you, and will therefore be exalted that he may have mercy upon you: because the Lord your God is a judge: blessed are they that stay themselves upon him.

The Brenton translation of the Septuagint is in the public domain.