Those who have disdain in their hearts for their brother must be deprived of love. Jesus taught that hate is the same as murder. The life of Jesus, eternal life, cannot abide in us if we hate others. Do we detest any of our fellow Christians, or for that matter, anyone else? How can we say that we are a Christian if we have any hate in our hearts and do not have love for our fellow man?
In verses 15-16:
John repeats Jesus' words that anyone who loathes someone else is a killer and a murderer in his or her heart. (Matthew 5:21-22; John 8:44; Galatians 5:21) Christianity is in the heart; outward consistence alone is not sufficient. Harshness or harboring any ill will against somebody who has wronged you is an insidious disease inside you and will eventually annihilate you. We are to try not to let a base of harshness develop within us or in our congregation. (Hebrews 12:15)
Genuine love is an activity, not an inclination. Sacrificial and selfless giving is what love creates in us. The best demonstration of love that anybody can do is to give himself for other people. How might we lay our lives down for another? At times it may be simpler to state we will give our lives for others than to genuinely live for them, which includes putting the wants and needs of others first. Dying may seem easy but living for someone else is much harder.
Jesus instructed this rule of love in (John 15:13; John 3:16). We can also look at Romans 5:8 and Ephesians 5:2.
In verses 17-18:
These verses give a demonstration of how to set out our lives for other people. Christians must show their love, and one approach to do that is to give financial or material belongings to help address other people’s issues. This is strikingly like James' lessons (James 2:14-17). How obviously do our activities state that we genuinely love others? Is it true that we are as liberal as we ought to be with our money, time, and assets? We should offer what we have to the individuals who need it (Luke 3:11; 1 John 4:20; Romans 12:9).
That does not mean blindly giving anyone anything. We are to pray for individuals and let the Spirit guide us in how and what to give. One person may need a little bit of financial support but that does not mean that we continually fork over money every time they call.
In verses 19-20:
Many are apprehensive that they do not love others as they ought to. They may feel regretful on the grounds that they think they are not doing enough of what is needed to demonstrate the legitimate love of Christ. So, their conscience begins to irritate them. John had these individuals as a primary concern when he composed this letter. How do we get away from the biting allegations of our own conscience? We should not disregard them or justify our conduct; we should set our hearts to rest in God's affection. (Romans 12:9)
If we feel regretful, we ought to remind ourselves that God sees our hearts and our activities. Our conscience is not as strong as God’s voice of assurance. If we keep ourselves in Christ, he will not denounce us (Romans 8:1; Hebrews 9:14). If we are living for the Lord yet feel we are sufficiently bad, we should remind ourselves that God is greater than anything.
In verses 21-22:
We can come to God unafraid, assured that our requests will be heard, if our conscience is clear. John reaffirms the promise that Jesus gave, “Ask and it shall be given you” (Matthew 7:7). When we obey, we ask in accordance with God's will. This does not imply that we can have anything we want. If we are genuinely looking for God's will, there are a few solicitations that we will not make (Matthew 21:22; John 9:31; James 5:16)
In verses 23-24:
We are to believe on the name of Jesus and in his person as the Son of God. Believing on the name of Jesus signifies that we design our lives after Jesus, to be more similar to him by joining ourselves with him. Dwelling in Christ is a fundamental relationship that shows itself in Christians who keep three basic orders.
o Belief in Christ
o Love the brethren
o Live a moral life
The presence of the Spirit is not only spiritual but practical. His presence is verified in our conduct (Romans 8:9; 1 John 2:3; 1 John 2:5; 1 John 2:27).
