zealous 2707 /kataphrontḗs ("a zealous person") is used of "one who is deeply committed to something and therefore zealous – 'enthusiast, zealous person'
In today's current usage Zealot comes with a negative connotation. But in the Bible it was a positive meaning.
In 2 Kings 19:31 and Isaiah 31:32 we are told that it is the zeal of the Lord that will call out a remnant.
In Psalm 69:9 we are told that a zeal for the Lord will consume us.
1 Corinthians 14:12 they were zealous for spiritual gifts.
Titus 2:14 says believers are zealous for good works.
Romans 12:11 instructs us to never lack zeal in serving the Lord.
So if an unbeliever says you are zealous or even over zealous, rejoice for you are being obedient to His word!