When men choose to reject the truth, God tends to withhold further truth from them. The result is spiritual and intellectual darkness.
Christianity was never intended to be made up of mindless and robotic men and women. People can come to different conclusions without being sinful in doing so.
Strength is not tested or demonstrated during times of ease. Rather, it is during times of adversity that one finds out just how strong he is.
Sin causes a man's strength to fail. On the contrary, "the way of the LORD is strength to the upright." Man's choice to sin will eradicate his strength.
Why would the Lord invite those weary from labour to wear a yoke? And then, why would the Lord promise rest by inviting people to labour?