Sacred Heart Gems - Daily Wisdom on the Heart of Jesus

The Marian Fathers and, more importantly, the magisterium of the Catholic Church teach that there is no contradiction or competition between the message of the Sacred Heart as revealed to Saint Margaret Mary Alacoque and the Divine Mercy message and devotion as revealed to Saint Faustina Kowalska.
Devout Catholics know this. After all, it's the same Jesus who revealed His Sacred Heart to Saint Margaret Mary Alacoque and, centuries later, revealed the Divine Mercy message and devotion to Saint Faustina Kowalska.
While each respective message has a distinct emphasis — for example, the message of the Sacred Heart focuses on reparation while the Divine Mercy Message and Devotion focuses on living a spirituality of trust in God's unfathomable mercy — each message comes from the same source, the Divine Person of Jesus Christ.

There are lots and lots of other saints, blesseds, venerables, servants of God, and popes who loved the Sacred Heart and wrote about it.
Each of the 366 days contains an invocation from the Litany of the Sacred Heart of Jesus.