Abel and Cain were brought up by the same parents; they grew up in the same family. However, their stories are diametrically different.
Genesis 4:1-5
Now Adam knew Eve his wife, and she conceived and bore Cain, and said, “I have acquired a man from the LORD.” Then she bore again, this time his brother Abel. Now Abel was a keeper of sheep, but Cain was a tiller of the ground. And in the process of time it came to pass that Cain brought an offering of the fruit of the ground to the LORD. Abel also brought of the firstborn of his flock and of their fat. And the LORD respected Abel and his offering, but He did not respect Cain and his offering. And Cain was very angry, and his countenance fell.
Although Abel lived a short life, he lived his life well. He brought his first and best fruit to the Lord. This passage tells us that obeying God is a choice. Unfortunately, sometimes despite knowing the right thing to do, we choose to go against the will of God. We also take God for granted and bring Him our worst or leftovers.
Being righteous is a choice. Abel committed his life to the way of God no matter what happens.
Hebrews 11:4
By faith Abel offered to God a more excellent sacrifice than Cain, through which he obtained witness that he was righteous, God testifying of his gifts; and through it he being dead still speaks
The life of Abel also teaches us that faith is not just a deep or warm feeling inside of us. It is not just a belief in God, but it is a living faith demonstrated through actions.
We need to remember that faith without works is dead (James 2:14-26). It is far useless to believe in God whilst our actions speak otherwise. Faith grows through doing and not simply believing alone. Of route, faith starts with believing in God (Hebrews 11:6). But, faith must go past only a mere belief. It needs to be active, alive, and thriving. This is the kind of faith that we should strive for.
Here is some food for thought:
Are we offering our first and best fruit—time, talents, resources—to God, and are we doing it in faith?