What is the remedy for absentmindedness during prayer? Is it permissible to marry and consummate the marriage with a girl twelve years of age who has not yet reached puberty, and what is the ruling of the Sharia on this? Is abstaining from masturbation five months before marriage sufficient to remove its effects? And what is the reason for the feeling that prayers are rejected and not accepted?

To address wandering thoughts in prayer, please refer to fatwas no. 33035 and 34584. There is no objection to marrying the person you mentioned and consummating the marriage if she is capable of intercourse. Usually, a girl who reaches twelve years of age is capable of intercourse, although this varies from one girl to another. Please refer to fatwa (definition) no. 21361. Masturbation is forbidden, and whoever practices it must immediately repent by abandoning it, regretting it, and resolving not to return to it. Please refer to fatwa no. 33352. If by "effects" you mean physical effects, then ask medical professionals about them. If you mean sins, then a sincere penitent from sin is like one who has no sin, as stated in Sunan Ibn Majah, and it is obligatory to abandon the sin immediately. Your feeling that your prayer is not accepted is a whisper from Satan, so do not pay attention to it. Perfect your prayer and have a good opinion of Allah. Please refer to fatwa no. 34216.