What is the ruling on having multiple intentions in customary acts, and is it sufficient to have the intention once, or must it be repeated with every act?

Intention is great; it transforms habits into acts of worship. It is a wondrous transformer that makes ordinary deeds enduring if a servant intends a good intention by them, such as intending to gain strength through food for the obedience of Allah, or preserving one's chastity through marriage and seeking righteous offspring. These deeds then turn into good deeds. This is indicated by the saying of the Messenger of Allah, peace and blessings be upon him: "When a man spends on his family, hoping for reward, it is charity for him." Attaining this reward requires presence of heart, and it is not difficult for one for whom Allah makes it easy. The condition for this is that the Muslim intends a good intention at the time of the action. So, for example, whenever he eats, he should intend a good intention, based on the saying of the Prophet, peace and blessings be upon him: "Indeed, actions are by intentions." If he does not intend a good intention, he will not have a reward. And even if the matter is difficult at first, with perseverance, it becomes easy and facilitated, in accordance with the saying of Allah the Almighty: "And those who strive for Us - We will surely guide them to Our ways. And indeed, Allah is with the doers of good."