"But solid food is for the mature, for those who have their powers of discernment trained by constant practice to distinguish good from evil." Hebrews 5:14 (ESV)
There is a difference between trying and training. trying means to exert effort at your current level of strength and ability. Training is the process of increasing your current level of strength and ability through discipline and repetition.
Jesus never asks us to try harder, but He does invite us to train (Matthew 11:29). At the beginning of every season, when I wrestled, I would be out of shape. My strength and stamina were less than desirable for what was needed to wrestle an intense 7-minute match. But without fail, in those early season practices, I would try and exert more strength and attempt to get my lungs to supply my body with greater amounts of oxygen (which is impossible) so my muscles wouldn't' fatigue. And without fail, I would be surprised at my body's inability to follow through.
But without consistent training, I was only kidding myself. I should have never expected my body to perform at such a high fitness level without the required fitness training beforehand. Trying harder was not going to help me in those early practices, but training would, and did.
The same is true for us spiritually. We think by trying hard not to lie that we can make our spiritual and moral muscles do what we want them to. Just like this is impossible physically, it is also impossible spiritually. So what are we to do? What are we to do when the temptation to lie is before us. How can we get to a place in our walk with Jesus, that we actually walk like Jesus?
We need to train with Jesus, not try harder (on our own and with our own strength). We need to spend time daily with Jesus through the following spiritual growth exercises:
Meditating and memorizing God's Word
Cultivating sincere relationships with other Believers
Ministering to others (service)
Living a life of devotion to Jesus in every area (worship)
When we spend time with Jesus in spiritual exercises (training), we will experience the results we were desiring in the first place. We won't have to try harder to experience peace, peace will become a natural result of our being with Jesus regularly.
Lord Jesus, give me the grace to understand that trying harder is not the answer, but training is. Simply spending regular time with you (Abiding) so that your character naturally flows from my life. Amen