Al-Kāfi

Hadith 1020
worship
8ـ مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنْ حَمَّادٍ عَنْ حَرِيزٍ عَنْ زُرَارَةَ قَالَ قَالَ أَبُو جَعْفَرٍ (عَلَيْهِ الْسَّلام) اعْلَمْ أَنَّ أَوَّلَ الْوَقْتِ أَبَداً أَفْضَلُ فَعَجِّلْ بِالْخَيْرِ مَا اسْتَطَعْتَ وَأَحَبُّ الأعْمَالِ إِلَى الله عَزَّ وَجَلَّ مَا دَاوَمَ الْعَبْدُ عَلَيْهِ وَإِنْ قَلَّ.
8. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from Hammad from Hariz from Zurarah who has said the following: “Abu Ja’far (a.s.), has said, ‘You must note that the beginning of time always is better, so act faster for the good as much as you can. The most beloved of deeds in the sight of Allah, most Majestic, most Glorious, is that which a servant continues even if it is very little.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī