Judging Others

I have been told things like this, numerous times by World Mission Society Church of God members:
"You say you love God, but you really don't! If you loved God, you would do what He says. You don't do what He says, so you don't really love Him. If you love God, why don't you do what He says?"

They will quote Luke 6:46, "“But why do you call Me ‘Lord, Lord,’ and not do the things which I say?"

By "doing what God says" they specifically mean that I should be
* going to church on Saturday (not Sunday)
* celebrating Passover (that is, the Lord's Supper only on the special night of Passover, not any other night or more than once a year)
* keeping all the Old Testament feasts of God
* NOT celebrating Christmas or Easter

The WMSCOG and its members claim that they follow all the Words of God, that they do keep all God's commands, and so they are the ones who truly love God (or "gods" I should say, because they have 2 of them).

Jesus said, in Matthew 7:1-2, "“Judge not, that you be not judged.  For with what judgment you judge, you will be judged; and with the measure you use, it will be measured back to you."

Yes, when we see sin, we can call it what it is, sin. But we MUST be careful about judging the motives and hearts of others--that's God's job. When you judge others harshly, you open yourself up to being judged yourself with the same measure.

If the WMSCOG wishes to judge others by this measure ("You don't really love God! Why do you not do what He says?"), I will take that measure and turn it around to them.... Do you always do everything that God says?...

I want to explore legalism and grace next. Legalism is doctrine that our salvation, our way into heaven, is gained through the things we do, our works, following the laws and commandments of God. Grace, however, is mercy and favor freely given by God, not earned by what we have done, but by faith in Who we believe. How do we enter heaven--by grace or by works?

Romans 3:21-24 (NIV)
21 But now a righteousness from God, apart from law, has been made known, to which the Law and the Prophets testify. 22 This righteousness from God comes through faith in Jesus Christ to all who believe. There is no difference, 23 for all have sinned and fall short of the glory of God, 24 and are justified freely by his grace through the redemption that came by Christ Jesus.