2 Corinthians 10:3-5 (KJV)
3 For though we walk in the flesh, we do not war after the flesh:
4 (For the weapons of our warfare are not carnal, but mighty through God to the pulling down of strong holds;)
5 Casting down imaginations, and every high thing that exalteth itself against the knowledge of God, and bringing into captivity every thought to the obedience of Christ;
Here walking in the flesh is not in a theological sense (ie. related to committing sin) but refers to us using our natural human abilities (physiologically). For example, we need to walk to go form A to B and to prepare food we use our bodies.
There is a spiritual war happening that can also become evident in the physical realm. There are demonic forces that influence people and try to influence us. These usually come though the mind trying to gain influence. Therefore we are to war against them in the spiritual realm and not the physical. If we were to fight them physically i.e. this would not deal with the underlying problem and be only a bandaid solution and impacting someone who was controlled by a demonic force.
In Ephesians Paul puts the spiritual fight as follows: “Ephesians 6:10-13 (KJV) Finally, my brethren, be strong in the Lord, and in the power of his might. 11 Put on the whole armour of God, that ye may be able to stand against the wiles of the devil. 12 For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places. 13 Wherefore take unto you the whole armour of God, that ye may be able to withstand in the evil day, and having done all, to stand.”
When Jesus was crucified, I believe, the people were influenced by the rulers of darkness. “Genesis 3:15 (KJV) And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel.” This, I believe, talks about Jesus born of the Virgin Mary and the devil. Jesus Himself prayed for the people “Luke 23:34a (KJV) Then said Jesus, Father, forgive them; for they know not what they do…”.
There are two ways attacks can come:
1. When in our mind imaginations arise and things that exalt themselves against the knowledge of God (i.e. temptations) we are then to bring every one of these thoughts into captivity and bring our thoughts back to the obedience of Christ. This we do using the Word of God (see Matthew 4:1-6), focusing on Jesus Christ, praying, praising and worshipping the LORD GOD.  
2. When we are faced with difficulties through people, situations, or our loved ones face them, we are to first and foremost pray. When the source of it is from the demonic we then needed to war in the spirit and not against people using prayer, calling out to Jesus and using the armaments Jesus has given us (Ephesians 6:11-13), standing firm in our faith letting rattle us. 
Having said this, we always can ask GOD for wisdom too. There are also times we need to take physical steps. We can also talk to and pray with other brothers and sisters who we trust and seek guidance that way.
Be encouraged “1 Corinthians 15:57-58 (KJV) But thanks be to God, which giveth us the victory through our Lord Jesus Christ. 58 Therefore, my beloved brethren, be ye stedfast, unmoveable, always abounding in the work of the Lord, forasmuch as ye know that your labour is not in vain in the Lord.”

For more on this see: 

“Our Warfare Continued – 2024.06.27” https://missioncommunities.network/2024/06/27/our-warfare-continued-2024-06-27/
“Time to be strong and courageous – 2024.06.25” https://missioncommunities.network/2024/06/25/time-to-be-strong-and-courageous-2024-06-25/
“Watch and pray – 2024.06.24” https://missioncommunities.network/2024/06/24/watch-and-pray-2024-06-24/
“Making hard and big decisions – 2024.06.02” https://missioncommunities.network/2024/06/02/making-big-decisions-2024-06-02/