but if we [really] walk in the Light [that is, live each and every day in conformity with the precepts of God], as He Himself is in the Light, we have [true, unbroken] fellowship with one another [He with us, and we with Him], and the blood of Jesus His Son cleanses us from all sin [by erasing the stain of sin, keeping us cleansed from sin in all its forms and manifestations].

For this is the message which you [believers] have heard from the beginning [of your relationship with Christ], that we should [unselfishly] love and seek the best for one another;

This is His commandment, that we believe [with personal faith and confident trust] in the name of His Son Jesus Christ, and [that we unselfishly] love and seek the best for one another, just as He commanded us.

Beloved, let us [unselfishly] love and seek the best for one another, for love is from God; and everyone who loves [others] is born of God and knows God [through personal experience].

Beloved, if God so loved us [in this incredible way], we also ought to love one another.

No one has seen God at any time. But if we love one another [with unselfish concern], God abides in us, and His love [the love that is His essence abides in us and] is completed and perfected in us.