First, in response to the OP, I believe that Paul answers the question perfectly in Romans 1:20, as was previously stated. Looking at God’s creation is sufficient to point to the average person that this did not all come into being by chance, and that there is an authority higher than oneself. This leads to one of three things, the rebellion of atheism, the resignation of agnosticism, or the resolution to seek out this higher being.
God gave many object lessons to the Old Testament saints. He slayed an animal to provide clothing for Adam and Eve, He provided a sacrifice for Abraham and Isaac, etc. All of these object lessons pointed to one thing: without the shedding of blood there is no remission of sin. I believe that the Old Testament saints were saved by looking forward to that ultimate sacrifice, just as we can now be saved by looking back to the ultimate sacrifice of Christ for our sins.
Not necessarily. If you accepted Christ as your Savior, you are saved. You should read your Bible, but you don’t have to. It isn’t a “works” salvation. But claiming Jesus as Lord isn’t enough (Mat 7:22-23 “Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? And then will I profess unto them, I never knew you: depart from me, ye that work iniquity.”). You have to repent and ask forgiveness from Christ (John 14:6 “Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me.”).
Have you honestly looked? Hint: It involves FAITH (Hebrews 11:6 “But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.”, emphasis mine).
The man who asked Jesus that question was a Pharisee, who only asked the question trying to tempt Christ. Here is the whole conversation:
Luke 10:25 And, behold, a certain lawyer stood up, and tempted him, saying, Master, what shall I do to inherit eternal life?
Luke 10:26 He said unto him, What is written in the law? how readest thou?
Luke 10:27 And he answering said, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy strength, and with all thy mind; and thy neighbour as thyself.
Luke 10:28 And he said unto him, Thou hast answered right: this do, and thou shalt live.
Luke 10:29 But he, willing to justify himself, said unto Jesus, And who is my neighbour?
Christ goes on to tell the parable of the good Samaritan (a class of people despised by the Jews of that time). My 2 cents is that if you love God with all your heart, soul, strength, and mind, you have pretty much accepted Christ as Savior, so Christ’s answer is (essentially) correct. I’m going to have to disagree with your interpretation of serving others taking the place of serving God, in so far as that interpretation implies far too much of a “works” salvation to make me comfortable. If we had to work to get into heaven, we’d never get there.
Oh come now. God doesn’t expect anyone to be perfect. I suggest you read the Bible and get a better handle on His teachings before you start spouting off on what God does and doesn’t want. To sum it up for you, God knows none of us are perfect. I personally fall short dozens of times a day. But Christ provided a way to be forgiven for all of our shortcomings. It’s really easy…you just have to admit that you have fallen short, realize that Jesus has provided forgiveness for you, and ask Him to forgive you. If you do that, and mean it, congratulations – you’re on your way to Heaven.