Question

why is the mind described swifter than the wind

Answer 1

The mind is described as swifter than the wind because it can race to the farthest corners of the earth and come  back, in a blink of an eye. The mind can also travel through our past and through the future faster and easily.
as ''The Rig Veda [10-58-12]  says that
Thy mind goes far awayTo all that occurred in the pastAnd will occur in the future,Call it back to thyselfSo that it may remainUnder thy control.