We can all cite many examples of those who do not follow through on their promises.
Spouses lie and cheat and marriages fall apart at the first sign of discomfort because we feel our promises aren't important. Business partners or co-workers break their word. Politicians frequently don't live up to their oaths of office; and neighbors and friends break their word and fail to arrive when they say they will, or do not back us up when we need them.
Jesus frequently elaborated on the Laws of Moses, telling those who would hear him that while most of them were following the LETTER of the Law, they were ignoring the SPIRIT of them. One such case was when Jesus spoke of oath-taking.
He said: "Again you have heard that it was said to those of old, 'You shall not swear falsely, but shall perform to the Lord what you have sworn.' But I say to you, Do not take an oath at all, either by heaven, for it is the throne of God, or by the earth, for it is his footstool, or by Jerusalem, for it is the city of the great King. And do not take an oath by your head, for you cannot make one hair white or black. Let what you say be simply 'Yes' or 'No'; anything more than this comes from evil." (Matt. 5:33-5:37.)
Arguably one of the most important things to Jesus was truth. "The Truth shall set you free," (John 8:32) wasn't just a throw-away line. He is repeatedly saying, "Truly, truly I say to you."
In the Parable of the Sower, it's the one who heard the word with an honest heart that brought forth good fruit with perseverance (Luke 8:15.) His disciples at one point said to him, "Teacher, we know that you are true and teach the way of God truthfully" (Matt. 22:16)
So if we believe this along with the disciples, we must believe that telling the truth was very important to Jesus. Simply swearing with one's mouth wasn't enough for him. It's easy to swear and then break your word. It's better, he said, to keep one's word without needing oath at all. And this makes sense. After all, who would force someone to take an oath if they had a reputation for always the truth?
This must have shocked some of those who heard Jesus. He had a way of saying things that were at first shocking and challenging. Some of his parables were not quickly understood. His call to be more righteous than the Pharisees wasn't a condemnation of evil people but a call to live more honestly than they had done (remember that he also said people should do as they say, but not as they do.)
But we can't fail to have high standards just because most people don't always uphold them.
If we look around we can see many who are seeking to be honest - those who keep their word, even when it hurts them to do so (Psalms 15:4.) Parents who teach their children to be honest and to never steal; shop owners who treat their customers and employees fairly, juries and judges who are truly impartial, business people who honor their commitments when it would be easy not to.
There are many who commit to keeping their "Yes" meaning "Yes" even without being forced to take oaths. THIS is the spirit Jesus wants us to have towards honesty!
And we can't doubt that such a strong commitment to honestly as Jesus holds up to us is possible, because Jesus has said God wishes us to live that way, and we have promised to follow our Master.
The Good News is that Jesus, himself lived this way sets for us an example - an example we know we can follow because he did it first. Let us hold his words, life and example as our high standard for honesty!