Question: "In this world where we are taught to enjoy ourselves and seek pleasure, where, even as Christians, we want to glorify God's creation, how are we to know when we have reached a level of overly enjoying the pleasures of the earth or of God's creation? I mean to say, if we are relaxing on the beach, or walking in wood, or gazing at the heavens, how do we know when enough is enough? It seems obvious we could or should all be working continuously for the Lord by praying or doing good works. But then it seems almost sinful to not enjoy the beauties of the world and God's creation as well. Is there a formula mentioned or something to help us know when enough is enough?"
There is not a simple formula. When you learn how to ride a bike, you have to learn how to balance your weight on the bike, while you peddle, but how do you do that? You do that by trying to do it, and when you fall down, you get back on the bike, and try it again.
There are some things that are inherently evil, and so there is no question but that we should abstain from such things. But it is not a sin to enjoy a good meal, or enjoy the company of another person. These are good things, but most good things can be taken to excess, and then it can become sinful.. but the sin is in the excess, not in the thing itself.
It can be an even better thing to abstain from such pleasures, if you are doing so out of love for God and a desire to draw closer to Him and to remove things that distract from that desire. But even asceticism can become sinful if it is seen as an end in itself or used as a means to vainglory.
It is also sinful if you abstain from things that are good, because you find them abominable. Canon 51 of the Holy Apostles says:
"If any Bishop, or Presbyter, or Deacon, or anyone at all on the sacerdotal list, abstains from marriage, or meat, or wine, not as a matter of mortification, but out of an abhorrence thereof, forgetting that all things are exceedingly good, and that God made man male and female, and blasphemously misrepresenting God’s work of creation, either let him mend his ways or let him be deposed from office and expelled from the Church. Let a layman be treated similarly."
So marriage is good. Eating meat is good. Drinking wine is good. However, if you abstain from these out of true asceticism, that is also good. But if you view these things as sinful in and of themselves, this view is itself sinful, and if not repented of will separate you from the Church.
So the key here is to find a balance. And what the right balance is will be different for different people.
In order to find that balance, you need to inform your conscience by regularly studying the Scriptures, the writings of the saints, and other edifying books. You need to keep the fasts of the Church. You should also pray that God will guide you, and go to confession regularly. And remember the words of St. Poemen the Great: "Everything that goes to excess comes from the demons" (Saying 129 of St. Poemen, from the Alphabetical Collection of the Sayings of the Desert Fathers).
You can listen to a sermon on some of the sayings of St. Poemen the Great which relate to this question, by clicking here.