Unfortunately Religion covers a lot of ground - but suffice to say in God's Word all but once it was used in it's worst case.
The Bible almost always uses it to signify a set of rules that men had laid down in addition to or to replace God's Word to the people on this world.
You will find in all false religions that ....
1. God's Word is either not there or given second place.
2. There will be a man (or organisation) in place that claims to have full knowledge and that the ordinary "man in the street" cannot possibly have the intelligence to understand the Bible. The Word of God states that the Bible is Spiritually discerned and all you need to understand the Word of God is the indwelling of the Holy Spirit - Christ in you heart. 1 Corinthians 2:14 But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know [them], because they are spiritually discerned.
3. The Rules are always changing! "New Light" continually being shed. One of the prophets will make a new announcements and it becomes dogma. The Word of God states in Hebrews 13:8 Jesus Christ the same yesterday, and to day, and for ever.. So religions that are continually changing their laws and rules are following some god - BUT NOT THE GOD OF THE BIBLE!
4. You will always have to do the best you can!
5. False religion only has tolerance for other religions when it is in the minority. Once they become part of the ruling class - or the Religion of the State - they become oppressive and actively seek out and persecute people of other religions (whether true Christian or not).
There are many more signs which I'll be posting as time permits - but all you really need to do is look at the countries where false religion is rife - the peoples that are massacred for not belonging to the state religion and THINK!
It may not seem like a big deal and it might even seem like the splitting of hairs but God has a severe warning for all those that would pervert His word in any form or fashion -
Revelation 22:8 For I testify unto every man that heareth the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book:
More good deeds, more persecution, give more, go more, do more, pray more, attend your place of worship more - in order to try and secure yourself a place in eternity. (And then you're still only hoping you've done enough!) It's interesting to note that the Muslim faith promises eternal pleasure in the arms of many young maidens - so does the Mormon faith - a planet of your own with many spiritual wives!?!
God's Word says over and over that Heaven is a free gift. Received by Faith Romans 3:28, Romans 5:1 and that nobody can take it from you John10:27-31, Romans 8:38,39
God's word asks for people to reason together with Him regarding their spiritual state (-Isaiah 1:18) it advocates the telling of the Gospel to everyone in the world - John 3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life. and Mark 16:15 And he said unto them, Go ye into all the world, and preach the gospel to every creature. Not at the point of a sword or through threats of personal injury, loss or death!
Revelation 22:19 And if any man shall take away from the words of the book of this prophecy, God shall take away his part out of the book of life, and out of the holy city, and [from] the things which are written in this book.
Revelation 22:20 He which testifieth these things saith, Surely I come quickly. Amen. Even so, come, Lord Jesus.