37  When Jesus had finished speaking, a Pharisee invited him to eat with him; so he went in and reclined at the table.
38  But the Pharisee, noticing that Jesus did not first wash before the meal, was surprised.
39  Then the Lord said to him, "Now then, you Pharisees clean the outside of the cup and dish, but inside you are full of greed and wickedness.
40  You foolish people! Did not the one who made the outside make the inside also?
41  But give what is inside [the dish] [55] to the poor, and everything will be clean for you.
42  "Woe to you Pharisees, because you give God a tenth of your mint, rue and all other kinds of garden herbs, but you neglect justice and the love of God. You should have practiced the latter without leaving the former undone.
43  "Woe to you Pharisees, because you love the most important seats in the synagogues and greetings in the marketplaces.
44  "Woe to you, because you are like unmarked graves, which men walk over without knowing it."
45  One of the experts in the law answered him, "Teacher, when you say these things, you insult us also."
46  Jesus replied, "And you experts in the law, woe to you, because you load people down with burdens they can hardly carry, and you yourselves will not lift one finger to help them.
47  "Woe to you, because you build tombs for the prophets, and it was your forefathers who killed them.
48  So you testify that you approve of what your forefathers did; they killed the prophets, and you build their tombs.
49  Because of this, God in his wisdom said, `I will send them prophets and apostles, some of whom they will kill and others they will persecute.'
50  Therefore this generation will be held responsible for the blood of all the prophets that has been shed since the beginning of the world,
51  from the blood of Abel to the blood of Zechariah, who was killed between the altar and the sanctuary. Yes, I tell you, this generation will be held responsible for it all.
52  "Woe to you experts in the law, because you have taken away the key to knowledge. You yourselves have not entered, and you have hindered those who were entering."
53  When Jesus left there, the Pharisees and the teachers of the law began to oppose him fiercely and to besiege him with questions,
54  waiting to catch him in something he might say.

Some say the second part of v.42 means there is New Testament support for a rule that says Christians should pay 10% of what they've got to the church.  The New English Bible (NEB) footnotes this verse as controversial, as if someone along the way wrote it in there themselves.  The NEB note says with regard to v.42, "Some witnesses omit It is ... others."  Notice how it doesn't even get it's own verse number; again, as if someone just tacked it on the end.

Try reading all the "woe" verses without that phrase:

42  "Woe to you Pharisees, because you give God a tenth of your mint, rue and all other kinds of garden herbs, but you neglect justice and the love of God.
43  "Woe to you Pharisees, because you love the most important seats in the synagogues and greetings in the marketplaces.
44  "Woe to you, because you are like unmarked graves, which men walk over without knowing it."
47  "Woe to you, because you build tombs for the prophets, and it was your forefathers who killed them.
52  "Woe to you experts in the law, because you have taken away the key to knowledge. You yourselves have not entered, and you have hindered those who were entering."

Notice how they all just describe a behavior pattern, none of them contain an instruction to the contrary.  Including the second part of v.42 breaks the smooth pattern, as if it shouldn't be there in the first place.

Think about it.  If a monk did just write it in himself, wouldn't it be easy for his boss to look the other way, take the money, and then rationalize it by saying the money would be used for God's work.  Monks didn't have very much, of course, neither did anyone else.

If it costs 10% to go to church, or any other taxation amount for that matter, lots of people are going to stay home.