Hawzah News Agency – The commander of the faithful, Imam Ali peace be upon him says:

فمِنَ الإيمانِ ما يكونُ ثابتاً مُسْتَقِرّاً في القلوبِ، ومِنهُ ما يكونُ عَوارِيَ بَينَ القلوبِ والصُّدوِر، إلى‏ أجلٍ معلومٍ.

'A part of faith is that which is firm and steadfast in the hearts, and another part is that which remains temporarily in the hearts and the breasts up until a certain time.'

Source: Nahj al-Balagha, Sermon 189