I don't understand, why the existence of aliens would be "against" God or His existence? Even if one day aliens come to Earth in front of everyone, it really would not bother my faith in God and Jesus at all. Is it all just because Bible doesn't mention it? I have 2 points about it:
1- Scriptures were made by people of a long, long time ago, they didn't even know the Earth was round and although they were inspired by God, He guided them to write in a way people of that time would understand with the knowledge from that era. For example, I don't remember exactly if it was on Leviticus or Numbers, but God guided Moses on how to treat some diseases, He could've used super advanced medicinal language if He wanted to or explained how to make a super effective medicine like the ones we have nowadays, but He explained in a way people of that period would understand. If aliens actually exist, that's why I think it doesn't go against Bible.
2- There is an specific passage on Bible that I personally like so much and I never saw people talking about or mentioning it. Jesus on John 3:12 says "If I have told you earthly things, and ye believe not, how shall ye believe, if I tell you of heavenly things?". It shows that there are heavenly things and about existence in general that we don't know and were not mentioned in the Bible.
What are your thoughts?
1 - I don't know if you fully realize it, but saying the scriptures were written long, long ago and those who written them had limited knowledge, greatly discredits the validity of the Bible. As a former skeptic and hater of God, I was very ignorant of the Truth of the scriptures, that I used this very argument to my advantage. I think most times, we don't give the ancient people enough credit and think we are way more advanced then them. For some reason the cave man image often comes to mind. We just assume they're less evolved based on what science (aka man) tells us, which is entirely false. Most ancient people were masters at whatever craft they took up, unlike most people today. Noah and his family built an amazing, enormous ship that was able to withstand a worldwide flood. Look at what ancient civilizations built and many things you'll find is astounding and incredible for people with less technology then us. The Bible also clearly states that in the end times, knowledge will increase. So what were seeing is no surprise as God stated this would in fact happen, but never does it make the scriptures from the past any less true. In fact, I think whatever knowledge comes about, will draw us closer to Jesus's return.
I also think an important thing to note is while we're here today trying to pick from the Bible what we accept as Truth and discard the rest to replace with our science, all of the prophets and apostles and righteous people of God, simply took Him at His Word. They had a fear of the Lord, which the Bible says is the beginning of all wisdom. And more then the knowledge we chase after today, many of them
did have wisdom. They also studied the scriptures day and night and knew them greatly by memory. It truly seems like in many ways, they let God be true and every man a liar. All this to say the ancient people were not perfect just as we aren't today. We're all just living and experiencing this fallen world together, past or present.
But with that being said, I think many of us 21st century people need to get off the high horse of our own understanding and humble ourselves before the True and Living God.
2 - When Jesus says heavenly things in this verse, the context is not referring to what is up in the sky (the sun, moon, stars). It's referring to God's dwelling place.