The Bible says that in order to worship God, you need a relationship with God.
In order that our spirit should worship God it should be alive which has been done when we accepted Christ as our personal Saviour.
Further, it is not possible to worship God either understand the things of God without our spirit having an interaction with the Spirit of God.
Man died spiritually(i.e. to say, his spirit died though it existed in him as a 'dead' spirit) when the first man Adam sinned. His spirit was then only made alive when he accepted the redemptive work of Christ on the cross.
How is it possible that the people who lived before Christ could worship Christ, if their spirit was dead ?... like Abraham, Job
Was it the sacrifices that they offered in the old testament that pointed out to the death of the coming Saviour on the cross, something that made their spirit alive?
1) Let's see what is the role of our spirit.
Our spirit is the only way by which we can have a relationship with God. God cannot be approached through our soul and feelings. It is only our spirit that can communicate to God. God is Spirit and they that worship him must worship him in spirit. When our spirit is dead, it is not possible to have a relationship with God. With our spirit dead, we are more like 'intelligent robots'.
2) How does our spirit communicate with the things of God or put in another way, with God himself?
The natural man (i.e. our dead spirit) cannot receive the things of the Spirit of God; neither can he know them; because they are spiritually discerned (1 Cor 2:14). Thus it is clear that we have to be spiritual (i.e. our spirit needs to be alive) to have a relationship with God.
Further it is the Spirit of God that teaches our spiritual man the things of God. We can never know the things of God unless the Spirit of God reveals them to us. But it is the Spirit of God that knows the things of God (1 Cor 2:11,13). There are certain things that we know of God which are freely given to us by him through the word of God (1 Cor 2:12). We can know these things only if the Spirit of God reveals them to us.
3) When is our spirit made alive?
Our spirit died when the first man Adam sinned against God. After that we see the second Adam i.e. Christ coming to this world and defeating Satan and sin and paving a new way to God or rather showing the world the only way to God. Anyone who accepts Jesus Christ as their personal Saviour becomes a child of God and the Spirit of God indwells in him. That is when the spirit is made alive.
4) How is the spirit made alive?
Rather than the redemptive work of Christ on the cross of Calvary, it was when we accepted Christ as our personal Saviour that our spirit was made alive by God. Note carefully, it was the faith that we had in Christ i.e. God that made our spirit alive. That is Justification by faith was the only way to God and the result of our faith, our spirit is now alive! Now who makes our spirit alive? Note that the Holy Spirit doesn't play any role in making our spirit alive. The new spirit is what God gives us (by the transformation of our old spirit through Christ) Ref. I Cor. 2:12.
5) What about the old testament times?
Well, Justification by faith was the only criteria to the way of God and that was the only way to God even in the old testament times.
We see Paul urging in his letter to the Hebrews, that it was only through the faith one had in God, were they saved and they could enter God's rest. We see in Hebrews that most of the Israelites didn't enter God's rest because of unbelief (Heb 3:18,19). God's rest here doesn't talk about the land of Canaan that God promised to the Israelites but heaven. We see God swearing to himself in his wrath that no one that believed in him could enter into his rest (Heb 3:11).
Also we see in Hebrews 11:6 that it is impossible to please God without faith. He who comes to God must believe (complete faith) that he is and that he is the rewarder of them that diligently seek him - the reward, salvation.
Apostle Paul further writes in Hebrews 3:14, that it is necessary to hold steadfast the faith that we have in Christ till the end.
The Israelites were such kind of people who believed God for their own gain and in their convenience. They turned to other gods when they didn't see all their wishes being fulfilled in Jehovah. That showed their faith wasn't steadfast with God and it wasn't consistent.
Till now we saw that even in the old testament times, Justification by faith in God held firm. And as we saw earlier that it was only through this faith that one's spirit was made alive in God and thus one could have a relationship with him.
6) So what is the answer?
Now answer to the question is yes, it was alive even in the old testament times but only through true faith in God. And that is how great patriarchs like Abraham, Job, etc, could worship God and have a relationship with him.
7) So what about the sacrifices in the old testament?
Sacrifices only depicted the work of Christ on Calvary. Through those sacrifices one could obtain forgiveness of his sins. It doesn't in anyway make your spirit alive. The latter can happen only through faith and not through fulfilling the law and it's works, i.e. through sacrifices.
8) What about the Holy Spirit?
We saw earlier that it was we can never learn the things of God unless the Holy Spirit of God teaches us those things.
In the old testament, I believe that the Spirit of God was there working among people though it didn't permanently reside within people's hearts. It only started residing permanently in the hearts of those who believed from the day of Pentecost. The Holy Spirit taught the things of God to only those whose spirit was made alive through faith on God. It is kind of stupid to say that the Holy Spirit wasn't working in the old testament times on this earth, because God himself is triune and works together in everything, though each one of the triune Godhead has a different responsibility.
9) What is the role of the Holy Spirit in the New Testament and the Old Testament?
While in the New Testament, we receive the Holy Spirit immediately when we accept Christ as our personal Saviour. The Holy Spirit as mentioned in the New Testament plays specific roles. Christ promised us him as a Comforter, in I Cor. we see him as a teacher, in Gal. we see him as a Shepherd, etc. While the role of the Holy Spirit in the New Testament is only for the edifying of the believers and nothing more, the Holy Spirit doesn’t play any role in our spirit being made alive. This is important to be understood if have to proceed further. Each person of the triune Godhead plays a specific role. It is God who gives us a new spirit while it is the Holy Spirit who works through our new spirit.
In the Old Testament, the Holy Spirit had specific roles to play. Leaving that point temporarily aside we will look at another important thing.
God communicates to believers (i.e. people who put their faith in God) through the Holy Spirit in the New Testament. He doesn’t communicate with us directly. We have a relationship with God because of the blood of Christ through the Holy Spirit. Note each of the three persons in the triune Godhead playing a different role.
In the Old Testament, God would directly communicate with his people. The Holy Spirit wasn’t required to have a relationship with God. We see God directly revealing his word to prophets and his elect. The Holy Spirit was sent only upon those people who had faith in God. The mission of the Holy Spirit was specific and not of that to establish a relationship of man with God. As we see in the book of the Judges, God first rising up his chosen. Then the Holy Spirit came upon the chosen when he had to be the judge of Israel (Judg. 3:9, 10). Since he already had a relationship with God (i.e. his spirit was alive through faith in God), God sent his Spirit upon him to judge Israel. The Holy Spirit was given for a specific purpose to the people. Its purpose being specific is seen in many incidents in the Bible. Bezaleel the son of Uri was filled with the Holy Spirit for the construction of the tabernacle (Ex.31:2, 3), the Spirit of the Lord was given to the seventy elders who was chosen by Moses for ruling Israel along with Moses (Num. 11:25), etc.
Secondly we see that the residing of the Holy Spirit wasn’t permanent as we read in the story of Samson that when he cut his hair, the Holy Spirit departed from him (Judg. 16:20). We read earlier that it had come upon him (Judg.13:25) and later when he accepted his mistake and realized his mission for Israel, the Lord strengthening him for the last time. The Holy Spirit was given to people as the power of God to help them do his service. It is obvious that God would choose only those people who had faith in him i.e. those whose spirit was alive in him.
As I end this discussion, I conclude by urging each one of us to recheck our faith and see where exactly our faith stands. Whether it can be drifted away by every wind of the world or whether it is firm in the sure foundation of the Word of God. Let’s strengthen ourselves in the Word of God wanting to know what exactly what God does teach through his word and learn from his word rather than depending on others.