"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." Luke 11: 42 (NIV)The problem with the Pharisees in this case is not that they were tithing. It is that they did so, thinking they were righteous in doing what was prescribed by God, while neglecting, Justice and Love of God, which was the purpose of the Law. The practice of tithing was specifically to express the love of God and to fund works of justice in the community. To give the tithe without practicing love and justice would be like donating to the Sierra Club, placing complimentary thank you bumper sticker on a gas guzzling vehicle, and throwing trash out the window as you drive. And Jesus' response is, prioritize the proper behavior, without forgetting to also give, as you had already done.
So yes, "Woe to the Pharisees," but also woe to us if we misread Jesus' words to say that one behavior is more important to the other--that is not what he is saying. Rather, let us not think ourselves righteous when we are only engaging in part of what is required. Let us not neglect the other things.
Of course, what the others things are depends on where we start and what we are talking about. For the person who is mission oriented, constantly serving in mission projects, etc., but does not practice any personal piety, reading scripture, praying, attending worship, etc.--Jesus' words are, start doing what you lack, without neglecting what you already are doing.
At times in the Church there are arguments about calls to holiness vs. grace. I often hear people say, "I'd rather error on the side of grace." Indeed, that is hard to argue with, but I also hear Jesus calling us always to righteousness, "I say to you that unless your righteousness is greater than the righteousness of the legal experts and the Pharisees, you will never enter the kingdom of heaven." Attend to the one without neglecting the other. We are formed both by a message of mercy, and a message of Righteousness. We are currently studying the book of Luke, where Jesus' ministry is clearly framed by John, "You children of snakes! Who warned you to escape from the angry judgment that is coming soon" Produce fruit that show you have changed your hearts and lives." (Luke 3: 7-8, CEB). And yet Jesus' has such great emphasis on grace and mercy shown to sinners. Why is that? We are called to one without neglecting the other.
Where are you excelling in your spiritual walk, and what do you need to be reminded not to neglect?