Hawzah News Agency – Imam al-Baqir peace be upon him says:

واللَّهِ، إنَّ أحَبَّ أصحابِي إلَيَّ أورَعُهُم وأفقَهُهُم وأكتَمُهُم لِحَديثِنا.

'By Allah, the most beloved of my companions to me are those who are the most pious, the most knowledgeable, and the most discrete with our speech.'

Source: al-Kafi. v. 2, p. 223, no. 7