Do you think people who claim to be Christians but never enter a church door to worship or tithe a dime are really christians? Their whole world revolves around themselves and family. I have close family members like this and am very concerned for them.
You have several mini-questions here, so let’s tackle each one.
First, you start out by asking my opinion about who might be a Christian, and who isn’t. Only God knows the heart of someone who has made an outward response to Christ. We know that some people who “look” like Christians really aren’t (Matt 13.38), but only God can tell the difference, not us.
However, we do know that obedience is a sign, an indicator, of those who are truly saved (1John 2.4). So we can safely make the observation that a person should certainly “evaluate” their profession of faith (Phil 2.12) if it is not accompanied by obedience.
So obedience is a crucial sign of true salvation. However, this must be obedience to God’s Word, bathed in the liberty we have in Christ – not shackled by religion or tradition that goes BEYOND God’s Word. We are bound only by Christ:
Galatians 5:1 Stand fast therefore in the liberty by which Christ has made us free, and do not be entangled again with a yoke of bondage. (NKJV)
Now, let’s take a look at the things you list: going to church, worshiping and tithing.
We are not commanded to “go to church“. We are commanded to “assemble” or meet together.
Hebrews 10:25 not forsaking the assembling of ourselves together, as is the manner of some, but exhorting one another, and so much the more as you see the Day approaching. (NKJV)
“Church” is the most common manifestation of this command – what we typically think of as a building or location where a group of Christians meet on a regular basis and this location becomes known as a “church”.
We are not commanded to “go to church”, we are commanded to NOT FORSAKE (purposely neglect or give up) the “assembling” of ourselves together to exhort (encourage) each other as we anticipate Jesus return. We find this was the habit of the early Christians:
Acts 20:7 Now on the first day of the week, when the disciples came together to break bread, Paul, ready to depart the next day, spoke to them and continued his message until midnight. (NKJV)
“Assembling” can be done in a building (what we commonly call a “church”), in a home, outdoors or anywhere that 2 or more Christians are gathered and Christ is there (Matt 18.20).
Simply failing to “enter the door of a church” does not necessarily constitute disobedience to God – forsaking the assembly of fellow Christians certainly does.
The “worship” issue is a little easier to answer. We are obviously commanded to worship God countless times in Scripture. A person whose life is devoid of worship to God certainly should be concerned about the authenticity of their salvation. However, “church” is not the only place worship can occur. It can occur in any “assembly” or in private worship.
Concerning “tithing“, as New Testament Believers, God tells us:
2 Corinthians 9:6-8 But this I say: He who sows sparingly will also reap sparingly, and he who sows bountifully will also reap bountifully. So let each one give as he purposes in his heart, not grudgingly or of necessity; for God loves a cheerful giver. And God is able to make all grace abound toward you, that you, always having all sufficiency in all things, may have an abundance for every good work. (NKJV)
There is much argument about whether or not Christians are bound by the “tithe” – but there is no doubt we are commanded to give. A Christian who never, or rarely, or grudgingly gives to God certainly should do some soul searching about their salvation.
Philippians 2:12 Therefore, my beloved, as you have always obeyed, not as in my presence only, but now much more in my absence, work out your own salvation with fear and trembling; (NKJV)
Again, obedience is tied closely to salvation. Obedience is evidence of true salvation and we can use it to evaluate our spiritual state.
When we observe other people, it is perfectly reasonable to be concerned about someone’s salvation who has no visible demonstration of obedience… but we must be careful that we are judging that obedience by God’s Word – and not by our religious tradtion, ignorance or bias.