The bible passage comes from Matthew 22:14. From the NIV:
Jesus spoke to them again in parables,
saying: "The kingdom of heaven is like
a king who prepared a wedding banquet
for his son. He sent his servants to
those who had been invited to the
banquet to tell them to come, but they
refused to come.
Then he sent some more servants and
said, 'Tell those who have been
invited that I have prepared my
dinner: My oxen and fattened cattle
have been butchered, and everything is
ready. Come to the wedding banquet.'
But they paid no attention and went
off—one to his field, another to his
business. The rest seized his
servants, mistreated them and killed
them. The king was enraged. He sent
his army and destroyed those murderers
and burned their city.
Then he said to his servants, 'The
wedding banquet is ready, but those I
invited did not deserve to come. 9Go
to the street corners and invite to
the banquet anyone you find.' 10So the
servants went out into the streets and
gathered all the people they could
find, both good and bad, and the
wedding hall was filled with guests.
But when the king came in to see the
guests, he noticed a man there who was
not wearing wedding clothes. 'Friend,'
he asked, 'how did you get in here
without wedding clothes?' The man was
speechless.
Then the king told the attendants,
'Tie him hand and foot, and throw him
outside, into the darkness, where
there will be weeping and gnashing of
teeth.'
For many are invited, but few are
chosen.
The guests do not enter the wedding hall immediately. Those gathered from the highways would be inappropriately clothed, so time is given them to clothe themselves in proper attire provided by the king (Isaiah 64:6; Zechariah 3:3-4). The parable suggests that, not only did the man not have on a wedding garment, but he did so intentionally. He decides against clothing himself properly, even though the appropriate clothing is available. His presence at the wedding is a sign of his rebellion against the king's authority and majesty, symbolized by the feast. When the man realizes his sin against the king's order, he is speechless as his judgment is pronounced.
The wedding garment, conspicuous and distinctive, represents a person's righteousness. It symbolizes the habit of sincerity, repentance, humility, and obedience. It replaces the street clothes that stand for the habits of pride, rebellion, and sinfulness. Biblically, beautiful clothing indicates spiritual character developed by submission to God (Revelation 3:4-5; 19:7-9). Paul exhorts Christians to "put on the Lord Jesus Christ" like a garment (Romans 13:14). Clothing, then, represents a Christ-covered life, and as a result, character consistent with God's way of life.
http://bibletools.org/index.cfm/fuseaction/Bible.show/sVerseID/23887/eVerseID/23887
As to it choosing you, maybe that is a function of your spiritual growth up to this lifetime. Personally, I have always been drawn to spiritual books and concepts, even though I am strongly analytical in nature. I was agnostic until I realized the songs that I composed were not really coming from me.