O believers! Whoever among you renounce Islam let him do so; soon Allah will replace them with others whom He will love and they will love Him, who will be humble towards the believers, mighty against the unbelievers, striving hard in the way of Allah, and do not fear the blame of a critic. Now this is the grace of Allah which He bestows on whom He pleases. Allah has boundless knowledge.
Meaning:-
Renounce: reject, deny, leave, to give up
critic: detractor, attacker, fault-finder,
Strive make great efforts to achieve or obtain something, struggle or fight vigorously.
Bestow: an honor, right, an honor, to present as a gift