Fasting is when you abstain from eating food for a period of time longer than you normally would.

In Biblical times people ate two meals a day.

The first being breakfast, which would be eaten
from anywhere between midmorning to noon. This meal is called breakfast because you
would break your fast since the previous days meal. Though you weren't actually considered to
be fasting until you skipped this meal. This meal was always the lighter meal of the day.

The next meal was supper. Supper was the main & heavier meal of the day.
It was eaten after the days work was finished, around the time of sunset, so that the heat
of the day was dissipating and people could cool off, relax and enjoy their meals.

In the Bible, people would fast during times of mourning, affliction & persecution.

Typical fasts last 1 to 2 days.

Jesus said that his disciples would not fast while He was with them, but when He was taken away, then
they would fast.
For this with the spirit of God indwelling in them, fasting brings us closer to His presence.
It is a powerful tool we can use to draw closer to God and view our lives in a magnified point of view.
During a fast it is easier to see anything in our lives that is contrary to God's perfect will.
Thoughts and ideas flow much easier when you fast.

This is why the early church dedicated two days a week to fasting.