The textual proof that Faith increases and decreases

Allah, the Almighty says: {that they may grow more in Faith along with their (present) Faith}. (Al-Fath, 4)
Allah says: {...and We increased them in guidance}. (Al-Kahf, 13) Allah says: {And Allah increases in

guidance those who walk aright}. (Maryam, 76)
Allah says: {While as for those who accept guidance, He increases their guidance}. (Muhammad, 17)
Allah says: {..and that the believers may increase in Faith}. (Al- Muddaththir, 31)
Allah says: {As for those who believe, it has increased their Faith}. (At-Tawbah, 124)
Allah says: {...therefore, fear them." But it (only) increased them in Faith}. (Al' Imran, 173)
Allah says: {And it only added to their Faith and to their submissiveness (to Allah)}. (Al-Ahzab, 22)
The Prophet (Peace be upon him) says: "By Him in Whose Hand is my life, if your state of mind remains the same as it is in my presence and you are always busy in remembrance (of Allah), the Angels will shake
hands with you in your beds and in your paths but, Hanzala, time should be devoted (to the worldly affairs) and time (should be devoted to prayer and meditation). He (the Holy Prophet) said this thrice ". (Sahih Muslim)