Asalamu alaykum wa rahmatullahi wa barakatuhAbout a month ago i painted walls, i washed my hands to get rid of the paint, made wudu and prayed. The next day i came to know that there was still a little bit of paint on my nail left from the day before and the water couldnt reach this spot. What should i do?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Ablution is not valid if water does not reach the nails because one of the conditions for the validity of ablution is that the limb that must be washed must be fully washed with water. This based on the Hadeeth narrated by Abu Daawood and others which states that "the Prophet saw a man praying and a part of his heel, equal to the size of the coin of a Dirham, was not washed by water (i.e., was dry), so he ordered him to renew his ablution and repeat the prayer."

The scholars of Fiqh concluded from this Hadeeth that whoever does not wash a part (as big as a coin) when washing the parts that are mandatory (for the validity of) ablution, whether he is certain of that or only doubtful that he left it, and he is not a person who suffers from whispers, then his ablution is void. If the interval (when discovering this after the prayer) is long, then he is obliged to repeat ablution and the prayer.

Hence, you should repeat the prayers that you had prayed with that ablution. You are not sinful as long as you did not do that deliberately.

For more benefit, please refer to Fataawa 91608 and 90386.

Allah knows best.