It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Holy Prophet (peace and blessings of Allah be upon him) said: Whoever among you comes for prayer should come with calmness and tranquility. Whatever part of the prayer he catches, he should perform, and whatever he misses, he should complete.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 7794
Hadith Gradingحکم دارالسلام:حديث صحيح، وهذا إسناد حسن في المتابعات، خ: 908، م: 602.