Q: Didn’t Jesus affirm life as a gift from God? Doesn’t that mean that we should enjoy life? Why then did Jesus speak of the need for suffering and self-denial?
A: Life is indeed a gift from God, and we are to enjoy it. But we are not to enjoy it in such a way that we become distracted from the spiritual dimension of life. People who live only for earthly pleasure and enjoyment tend to lose their focus on the spiritual side of life, involving God, morality, unselfish love, and eternity.
As a result, some form of self-denial is useful as a spiritual discipline to keep us from forgetting earthly indulgence is not the purpose of life. If we deny ourselves part of the material world, we make the point to ourselves (on an experiential, not just an intellectual level) that the material world is not to be the thing we live for and serve.
Thus Jesus does not glorify suffering for its own sake, but only as a means to get us to realize that earthly pleasures (the opposite of earthly sufferings) are not to be the most important thing in our lives and are not the principle by which we make all of our decisions. Jesus only endorses suffering and self-denial to the extent that it draws us closer to God, not as an end in itself.