In Surah Fatiha, Allah Almighty says:

غَيرِ المَغضُوبِ عَلَيهِمْ وَلاَ الضَّالِّينَ

Translation: Not of those who earned your anger, nor of those astray.

From this verse, scholars mention that we identify three levels of practice.

First, there are those who don’t know–they don’t know about Islam. They don’t know about the truth. Or they don’t know enough–for example, how to pay zakaah. These are the ones mentioned as gone astray (الضَّالِّينَ).

The second level is those who know, but do not practise. They know Islam is the truth, they might even claim to be Muslim, but they don’t pray, they don’t fast, they don’t enjoin good and forbid evil, they don’t follow the Sunnah–they don’t act on their knowledge. And while it’s true that they could also be as those astray, to be more correct, they are closer to those who earned Allah’s anger (لمَغضُوبِ).

The third level is those who know and practise what they know–the believing Muslims. May Allah make us all of that level, ameen!

So practise what you know–don’t just sit on it!  And remember, knowledge, unused, fades away.

References

Khutba Between Taraweeh Prayers. By Abu Owais Qais. Istiqamah Masjid, Mississauga. 27 Sept. 2006.