Verses with the word swiftly in the Old Testament (4 verses):

Psalms 147:15
He sendeth forth his commandment upon earth: his word runneth very swiftly.

Isaiah 5:26
And he will lift up an ensign to the nations from far, and will hiss unto them from the end of the earth: and, behold, they shall come with speed swiftly:

Daniel 9:21
Yea, whiles I was speaking in prayer, even the man Gabriel, whom I had seen in the vision at the beginning, being caused to fly swiftly, touched me about the time of the evening oblation.

Joel 3:4
Yea, and what have ye to do with me, O Tyre, and Zidon, and all the coasts of Palestine? will ye render me a recompence? and if ye recompense me, swiftly and speedily will I return your recompence upon your own head;