Romans 10.2 observes they were zealous for God but their zeal is not in line with the truth. Being zealous for God is good but a zeal for God that is not in accord with the ways of God is bad.

In the kingdom of God the ends does not justify the means. People are to serve God in the ways of God if they are going to please God.

The Muslim zealot who destroys the lives of innocent people through his suicide vest is an abomination to the One True God. While zealous for God his zeal is not in line with the truth.

Many people who pursue God do so according to their own means thinking that as long as they live a good life, by their own standard, God will be pleased with them.

But God is not pleased when we live apart from His commands. Feeling good toward God is not the same as loving God or obeying God.

God has come in Jesus the Christ to teach us what He requires from us. God has recorded for us everything we need in order to live lives pleasing to Him in the Bible so that people are without excuse on that day when He judges every person for how they lived in obedience to His commands.

There really is only one God, one way, one truth and we must align ourselves with Him if we would hope to pass from this life to the next and be accepted by God in His eternal kingdom. There are false religions and false religious books for the enemy of God seeks to keep people from loving God and from living according to His will.

God is not aloof, He very present, He has lived among us physically and He has recorded for eternity His character, His will and His ways so we could know Him and how we are to live.

God loves the zealous person who is zealous in accordance to His truth.