We may be able to fool a lot of people but we can't fool our moms and we can't fool Yahweh. Our moms have been studying us since the hour we were born. She has watched over us while we slept, watched us while we ate, watched us while we played. She knows what every facial expression means. She doesn't listen to our words as much as the tone in which they are spoken, our expression and our body language. But as good as moms are they are limited to what they see and hear, they don't actually know our heart. Yahweh, our Creator, knows our heart.
Yahweh once told the prophet/judge Samuel something important that he repeated on several occasions and that Jesus also taught concerning:
“Do not look at his appearance or his stature, because I have rejected him. Man does not see what the Lord sees, for man sees what is visible, but the Lord sees the heart.” (1 Samuel 16:7)
This should be both encouraging and frightening. It is encouraging that even when we mess up Yahweh knows the sincerity of our love for him. This is why he continued to favour David even when he had to severely correct David, because David was whole heatedly in love with Yahweh. He desired to live to please him even though there were moments of colossal failure. That should teach us something concerning our relationship with Father and his love.
On the other hand, if we are faking it, Yahweh knows. We cannot mock him. If we are trying to live a good life with no real relationship with Jesus, he knows. Salvation isn't about being good or being kind; salvation is about accepting and receiving the sacrifice of Jesus for us. It is something born out of conviction and repentance. It is the most honest and real moment of our lives. Yahweh knows the difference between a sincere and insincere heart.
Jesus taught a great deal on the heart condition. He taught us that it is the place where we harbour sin before it is acted on. He taught us:
“What comes out of a person—that defiles him. For from within, out of people’s hearts, come evil thoughts, sexual immoralities, thefts, murders, adulteries,greed, evil actions, deceit, promiscuity, stinginess, blasphemy, pride, and foolishness. All these evil things come from within and defile a person.” (Mark 7:20-23)
Along the same lines he stated:
A good man produces good out of the good storeroom of his heart. An evil man produces evil out of the evil storeroom, for his mouth speaks from the overflow of the heart. (Luke 6:45)
We may think we are fooling everyone but Yahweh knows and in the end he is the only one who matters. As much as our moms and dads love us, they cannot save us. As much as our friends may love us, they cannot save us. As much as the world may appreciate us, it cannot save us. Salvation is only through Jesus, who loves us more than everyone combined. But do you love him? Do you love him with all your heart? Do you love him enough to obey him? Even in your failings, do you desire to live exclusively for him? He looks for sincerity and he cannot be mocked. He knows your heart and by it he judges you.