Many believers in the Lord Jesus avoid too much exposure to the Old Testament. "It's too dry," they say, or, "It's too hard to understand." Such believers are missing out on some of the richest of God's teachings. True, some Old Testament wording is daunting, but who said we have to pronounce every single word we read? And true, Jesus fulfilled the Jewish ceremonial laws. But even though the Law of Moses no longer rules our behavior, each law God gave has an application to our lives in Christ Jesus.
Take, for instance, Exodus 20:25:
The alter was to be of earth, not of hewn stone. The verse expands on that idea with, for if thou lift up thy tool upon it, thou hast polluted it. The reason for that distinction is solely for our instruction. Do we build stone alters? Never! Since Jesus was the last sacrifice, there is no need for an alter of sacrifice in the church(Hebrews chapter 10). Hewing the stone for the alter symbolizes our unwarranted requirements for religious ritual, rules and prohibitions. When we enforce our own machinations upon our corporate religious practice, we profane the alter upon which we offer ourselves, rendering the offering profane as well.
Is that to say, as some do, that we must pattern our religious practices exactly after those of the apostolic church, or the synagogue, or even the temple worship? Of course not! That would place the emphasis of our worship upon formality, rather than upon our Savior. Instead, we are to worship as Jesus instructed the Samaritan woman: John 4:22-24 ESV You worship what you do not know; we worship what we know, for salvation is from the Jews. 23 But the hour is coming, and is now here, when the true worshipers will worship the Father in spirit and truth, for the Father is seeking such people to worship him. 24 God is spirit, and those who worship him must worship in spirit and truth."
Does that mean we must "worship in the Holy Ghost," including mandating "tongues" in our worship, as Pentecostals assert(1 Corinthians 12:27-31)? Or does it mean that we should prohibit speaking in tongues(1 Corinthians 14:21-40)? Such requirements are nothing more than "hewing the alter-stones" on which we sacrifice ourselves. John 4:24 simply means our worship is to be spiritual, not ritualistic. Spiritual worship is concentrating solely on God, rather than on formality or program.
"Is Pastor Frank raising his hands in worship? Oh, yes he is. So I'd better do the same. But I'm embarrassed. What will people think of me? Maybe if I just sort of half-raise my hands, or lift only one hand, they won't think I'm trying to act spiritual." Those who entertain such concerns are nothing more than people-pleasers, and God has some strong things to say about that behavior(Eph_6:5-7, Luk_18:9-14).
All that is to say, "Don't sweat it!" Worshiping is to the believer as breathing is to any animal. If you're a believer, you will worship. Concerns about worshiping according to custom or liturgy miss the point completely.
Neither studying the Old Testament, nor participating in worship, will be a dry experience to whose who are walking in God's Holy Spirit.