By the way, in case anyone else cares to chime in, here are the fasting regulations according to the ancient Christian tradition pertaining specifically to Lent (the 40 days before Pascha a.k.a. Easter): avoidance of all red meat, poultry, meat derived from all four-footed creatures, all dairy products (including milk, eggs, & cheese), olive oil and any oils derived by an extracted fashion. If anyone knows of something I didn't mention that should be included, feel free to add it.
Saint Matthew 4:1-4
Then Jesus was led up by the Spirit into the wilderness to be tempted by the devil.
And when he had fasted forty days and forty nights, afterward he was hungry.
Now when the tempter came to Him, he said, "If You are the Son of God, command that these stones become bread."
But He answered and said, "It is written, 'Man shall not live by bread alone, but by every word that proceeds from the mouth of God.'"
Saint Matthew 6:16-18
"[b]Moreover, when you fast, do not be like the hypocrites, with a sad countenance. For they disfigure their faces that they may appear to men to be fasting. Assuredly, I say to you, they have their reward.
But you, when you fast, anoint your head and wash your face, so that you do not appear to men to be fasting, but to your Father who is in the secret place; and your Father who sees in secret will reward you openly[/b]."
Saint Matthew 9:14-15
Then the disciples of John came to Him, saying, "Why do we and the Pharisees fast often, but Your disciples do not fast?"
And Jesus said to them, "Can the friends of the bridegroom mourn as long as the bridegroom is with them? But the days will come when the bridegroom will be taken away from them, and then they will fast."
Saint Matthew 17:14-21
And when they had come to the multitude, a man came to Him, kneeling down to Him and saying,
"Lord, have mercy on my son, for he is an epileptic and suffers severely; for he often falls into the fire and into the water.
So I brought him to your disciples, but they could not cure him."
Then Jesus answered and said, "O faithless and perverse generation, how long shall I be with you? How long shall I bear with you? Bring him here to Me."
And Jesus rebuked the demon, and it came out of him; and the child was cured from that very hour.
Then the disciples came to Jesus privately and said, "Why could we not cast it out?"
So Jesus said to them, "Because of your unbelief; for assuredly I say to you, if you have faith as a mustard seed, you will say to this mountain, 'Move from here to there,' and it will move; and nothing will be impossible for you. However, this kind does not go out except by prayer and fasting."
There are scores of passages in the Old & New Testament that highlight the necessity of fasting, but I chose a few from the Gospel according to Saint Matthew. I hope you all get the point. We walk with Jesus Christ by imitating Him (as He fasted on the mountain for forty days), we obey His command to adhere to fasting, and we fast because there's a clear spiritual strength and focus which the ritual provides.
Peace be with all!