Our Lady not only blesses those who preach her Rosary but she highly rewards all those who, by their example, get others to say it.
Alphonsus, King of Leon and Calicia, very much wanted all his servants to honor the Blessed Virgin by saying the Rosary, so he used to hang a large rosary on his belt, though he never said it himself. Nevertheless, his wearing it encouraged his courtiers to say the Rosary devoutly.
One day the King fell seriously ill and when he was given up for dead he found himself, in spirit, before the judgment-seat of our Lord. Many devils were there accusing him of all the sins he had committed, and our Lord was about to condemn him when our Lady came forward to speak in his favor. She called for a pair of scales and had his sins placed in one of the balances, while she put the large rosary which he had always worn on the other scale, together with all the rosaries that had been said through his example. It was found that the Rosaries weighed more than his sins.
Looking at him with great kindness, our Lady said, “As a reward for the little service you did for me in wearing my rosary, I have obtained a great grace for you from my Son. Your life will be spared for a few more years. See that you spend those years wisely, and do penance.”
When the King regained consciousness he cried out, “Blessed be the Rosary of the most holy Virgin Mary, by which I have been delivered from eternal damnation.”
After he had recovered his health, he spent the rest of his life in spreading devotion to the Rosary and said it faithfully every day.
Source: Miraculous Stories of the Rosary by Saint Louis de Montfort