Hazrat Mufti Mahmood Hasan Gangohi (rahimahullah) mentioned:

When we plant a sapling, we undertake great pains to protect it, either from being eaten by an animal or from wilting due to severe heat or from drying up due to severe cold. It is watered according to its requirements and it grows and produces fruit only when it is carefully tended to. The creation of Allah Ta‘ala takes benefit from its leaves, its branches, its flowers and its fruit. It becomes a tree of great value and benefit. But if it is not protected and nurtured, it will be destroyed and benefit no one.

Imaan is also a sapling, which has been planted within the heart. The reality of Imaan has been explained (in a verse of the Quraan Majeed) as ‘the resolve to lead one’s life according to Our divine law’.

It is of utmost importance to protect this sapling of imaan. When a sapling is well guarded, it becomes firm and strong. This protection of imaan is called taqwa, i.e. to protect the sapling of imaan from the disobedience of Allah Ta‘ala. (Discourses of Faqeeh-ul-Ummah Hazrat Mufti Mahmood Hasan Gangohi, vol. 1, pg. 117)