How did Mozart rearrange Handels Messiah?

Mozart rearranged Handel's "Messiah" in 1789, primarily to adapt the work for a smaller orchestral ensemble and to make it more suitable for the performance practices of his time. He reorchestrated the piece, modifying instruments and adding new parts to enhance the overall texture and sound. Additionally, Mozart's arrangement included some alterations to the original vocal lines and dynamics, reflecting his own stylistic preferences while maintaining the essence of Handel's composition. This version helped revitalize "Messiah" for a contemporary audience, contributing to its enduring popularity.