"Woe to you, scribes and Pharisees, hypocrites! For you tithe mint and dill and cummin, and have neglected the weightier provisions of the law: justice and mercy and faithfulness; but these are the things you should have done without neglecting the others. You blind guides, who strain out a gnat and swallow a camel!” (Mt 23: 23-24)
The scribes and Pharisees were meticulous about the smaller prescriptions of the law, like the prohibition, according to Leviticus 11, of eating any creature that “creeps along the ground.” So they would strain their wine and other liquids, to make sure there was no “gnat” or other small insect in it. At the same time, they neglected the whole point of the law, which was “justice, mercy, and faithfulness.” Christ is reminding them that they should be doing both: following the smaller, external rules, and embracing the “weightier,” inner meaning of those rules.
It is sometimes difficult to discern, on a daily basis, what is primary and what is secondary. I may set out, for example, to “improve” my prayer-schedule or fasting discipline, say, during this period of the Nativity Fast. At the same time, I may be neglecting some bigger, outstanding problem in my heart, like being stand-offish and arrogant certain colleagues at work, or a member of my family. Or perhaps I am engaging in self-loathing, ungratefulness, and dissatisfaction with life as it is. Or perhaps I ramble on and on about "Christian" political issues, while ignoring the state of my life in Christ altogether.
Now, the Lord is not telling me to ignore prayer, fasting, and outside issues. What He is, however, telling me, is that whatever external discipline I practice, I should all the time be focusing on the renewal of my heart in His Spirit; on my inner disposition to Him, myself, and others. Today let me ask for, and rely upon, His help and grace, keeping my heart open to Him and other “others” throughout my day.