I am a brother in Christ, but I have trouble understanding how Luke 21:25,26 and 1 Thessalonians 5:3 can both be right. How can they be saying peace and security and at the same time being fearful about the thing coming to the earth?
It’s a matter of timing. In 1 Thes 5:3 Paul was describing a short period of peace that will come just before the sudden destruction of Daniel’s 70th Week . I believe it will be the result of the battle of Ezekiel 38-39. Unbelievers will think it’s permanent but it will soon prove to very temporary.
Luke 21:25-26 speaks of signs in the sun, moon and stars and describes the time just after Daniel’s 70th Week begins. I believe Luke 21:25 corresponds to Rev. 6:12 where signs in the sun, moon and stars indicate that the time of God’s wrath has come (Rev. 6:16-17) and the worst series of judgments in human history will have begun.