My ancestors moved from West Tennessee to Northeast Arkansas in 1921. Soon after they arrived, a family member, Edd Hill, my Grandpa Marshall's brother-in-law, announced he would be gone for a while and would return someday. Months later he reappeared. He had traveled back to Tennessee to work off debts the family had left behind.
Our bare word should be as sacred to us as a solemn oath. Because we are committed to truth in our promises, we have nothing to fear by taking an oath before God. If called on to take an oath, Christ-followers are free to consent. Paul did. We will gladly put our hands on a Bible, but should not need to for the Bible is engraved on our hearts. If need be, we will lift our hand to Heaven, but should not need to because Heaven has been put in our innermost being.
Jesus taught us; the maximum regard we hold for the most sacred oath is to be the minimum standard for our bare word. If people make promises, God is always present and listening. We are to act like we believe this. Some religions teach it is okay to lie to outsiders. Some are okay with lying to the government. Christ-followers, though, make no such distinctions as words that have to be true versus words that do not have to be true.
I remember when people assumed honesty in interpersonal dealings. My Grandma Marshall once put a note on her front door, "Front door locked. Back door open." She missed the point. People had told her to lock her door. She did, but did not want people to think she did not trust them.