Strong is something that is not easy destroy, damage, modify, weak and is something that has one force that is better than the other forces. Strong is one quality of love that is very necessary for build one relationship. Love is strong because is unconditional and stay we our lifes until we die. Today people want what is weak, fake, casual, easy to get and dont care about be a human because a true human has one thing that is: affection. Like I say before affection is one sign of be human. The diference of be a human or animal is that for humans is very easy get affection and build connections. You can say: but casual dates is not show affection? No. No because in casual dates what only happen is sex, and behind these people do sex when they have casual dates they in reality dont show affection because one caracterists of have affection is mantein or miss or want stay with that person and not make "mecanic contact" and leave. Affection is you like one thing and you feels that you need that thing close of you. So, casual dates people meet one person stay with her some time and leave.For example in other post about the homosexuality and bible, homosexuality is not clear but what is clear is fornication. Is very simple understand why in bible God condenn fornication because people when do sex without feelings, affection, true desire, honor, they only have a simple contact that is use the body and leave.
This is easy understand and is not necessary read the bible for take conclution about affection and human contact. Other religions say the same, doesnt matter religion.
Strong is very necessary because in relationships when exist dificult times like for example, distance, death... if love is strong enough, then will survive and is one connection that is pure and human. Only what is strong has force, what is weak loose. Is not the "boy next door", "easy going", "casual" that has force enough for find love, because what has force enough is strong and is unconditional.

